4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2011, 2018 by Delphix. All rights reserved.
24 * Copyright (c) 2014 Integros [integros.com]
25 * Copyright (c) 2018 Datto Inc.
28 /* Portions Copyright 2010 Robert Milkowski */
30 #include <sys/zfs_context.h>
32 #include <sys/spa_impl.h>
38 #include <sys/zil_impl.h>
39 #include <sys/dsl_dataset.h>
40 #include <sys/vdev_impl.h>
41 #include <sys/dmu_tx.h>
42 #include <sys/dsl_pool.h>
43 #include <sys/metaslab.h>
44 #include <sys/trace_zfs.h>
48 * The ZFS Intent Log (ZIL) saves "transaction records" (itxs) of system
49 * calls that change the file system. Each itx has enough information to
50 * be able to replay them after a system crash, power loss, or
51 * equivalent failure mode. These are stored in memory until either:
53 * 1. they are committed to the pool by the DMU transaction group
54 * (txg), at which point they can be discarded; or
55 * 2. they are committed to the on-disk ZIL for the dataset being
56 * modified (e.g. due to an fsync, O_DSYNC, or other synchronous
59 * In the event of a crash or power loss, the itxs contained by each
60 * dataset's on-disk ZIL will be replayed when that dataset is first
61 * instantiated (e.g. if the dataset is a normal filesystem, when it is
64 * As hinted at above, there is one ZIL per dataset (both the in-memory
65 * representation, and the on-disk representation). The on-disk format
66 * consists of 3 parts:
68 * - a single, per-dataset, ZIL header; which points to a chain of
69 * - zero or more ZIL blocks; each of which contains
70 * - zero or more ZIL records
72 * A ZIL record holds the information necessary to replay a single
73 * system call transaction. A ZIL block can hold many ZIL records, and
74 * the blocks are chained together, similarly to a singly linked list.
76 * Each ZIL block contains a block pointer (blkptr_t) to the next ZIL
77 * block in the chain, and the ZIL header points to the first block in
80 * Note, there is not a fixed place in the pool to hold these ZIL
81 * blocks; they are dynamically allocated and freed as needed from the
82 * blocks available on the pool, though they can be preferentially
83 * allocated from a dedicated "log" vdev.
87 * This controls the amount of time that a ZIL block (lwb) will remain
88 * "open" when it isn't "full", and it has a thread waiting for it to be
89 * committed to stable storage. Please refer to the zil_commit_waiter()
90 * function (and the comments within it) for more details.
92 static int zfs_commit_timeout_pct
= 5;
95 * See zil.h for more information about these fields.
97 static zil_stats_t zil_stats
= {
98 { "zil_commit_count", KSTAT_DATA_UINT64
},
99 { "zil_commit_writer_count", KSTAT_DATA_UINT64
},
100 { "zil_itx_count", KSTAT_DATA_UINT64
},
101 { "zil_itx_indirect_count", KSTAT_DATA_UINT64
},
102 { "zil_itx_indirect_bytes", KSTAT_DATA_UINT64
},
103 { "zil_itx_copied_count", KSTAT_DATA_UINT64
},
104 { "zil_itx_copied_bytes", KSTAT_DATA_UINT64
},
105 { "zil_itx_needcopy_count", KSTAT_DATA_UINT64
},
106 { "zil_itx_needcopy_bytes", KSTAT_DATA_UINT64
},
107 { "zil_itx_metaslab_normal_count", KSTAT_DATA_UINT64
},
108 { "zil_itx_metaslab_normal_bytes", KSTAT_DATA_UINT64
},
109 { "zil_itx_metaslab_slog_count", KSTAT_DATA_UINT64
},
110 { "zil_itx_metaslab_slog_bytes", KSTAT_DATA_UINT64
},
113 static kstat_t
*zil_ksp
;
116 * Disable intent logging replay. This global ZIL switch affects all pools.
118 int zil_replay_disable
= 0;
121 * Disable the DKIOCFLUSHWRITECACHE commands that are normally sent to
122 * the disk(s) by the ZIL after an LWB write has completed. Setting this
123 * will cause ZIL corruption on power loss if a volatile out-of-order
124 * write cache is enabled.
126 static int zil_nocacheflush
= 0;
129 * Limit SLOG write size per commit executed with synchronous priority.
130 * Any writes above that will be executed with lower (asynchronous) priority
131 * to limit potential SLOG device abuse by single active ZIL writer.
133 static unsigned long zil_slog_bulk
= 768 * 1024;
135 static kmem_cache_t
*zil_lwb_cache
;
136 static kmem_cache_t
*zil_zcw_cache
;
138 #define LWB_EMPTY(lwb) ((BP_GET_LSIZE(&lwb->lwb_blk) - \
139 sizeof (zil_chain_t)) == (lwb->lwb_sz - lwb->lwb_nused))
142 zil_bp_compare(const void *x1
, const void *x2
)
144 const dva_t
*dva1
= &((zil_bp_node_t
*)x1
)->zn_dva
;
145 const dva_t
*dva2
= &((zil_bp_node_t
*)x2
)->zn_dva
;
147 int cmp
= TREE_CMP(DVA_GET_VDEV(dva1
), DVA_GET_VDEV(dva2
));
151 return (TREE_CMP(DVA_GET_OFFSET(dva1
), DVA_GET_OFFSET(dva2
)));
155 zil_bp_tree_init(zilog_t
*zilog
)
157 avl_create(&zilog
->zl_bp_tree
, zil_bp_compare
,
158 sizeof (zil_bp_node_t
), offsetof(zil_bp_node_t
, zn_node
));
162 zil_bp_tree_fini(zilog_t
*zilog
)
164 avl_tree_t
*t
= &zilog
->zl_bp_tree
;
168 while ((zn
= avl_destroy_nodes(t
, &cookie
)) != NULL
)
169 kmem_free(zn
, sizeof (zil_bp_node_t
));
175 zil_bp_tree_add(zilog_t
*zilog
, const blkptr_t
*bp
)
177 avl_tree_t
*t
= &zilog
->zl_bp_tree
;
182 if (BP_IS_EMBEDDED(bp
))
185 dva
= BP_IDENTITY(bp
);
187 if (avl_find(t
, dva
, &where
) != NULL
)
188 return (SET_ERROR(EEXIST
));
190 zn
= kmem_alloc(sizeof (zil_bp_node_t
), KM_SLEEP
);
192 avl_insert(t
, zn
, where
);
197 static zil_header_t
*
198 zil_header_in_syncing_context(zilog_t
*zilog
)
200 return ((zil_header_t
*)zilog
->zl_header
);
204 zil_init_log_chain(zilog_t
*zilog
, blkptr_t
*bp
)
206 zio_cksum_t
*zc
= &bp
->blk_cksum
;
208 (void) random_get_pseudo_bytes((void *)&zc
->zc_word
[ZIL_ZC_GUID_0
],
209 sizeof (zc
->zc_word
[ZIL_ZC_GUID_0
]));
210 (void) random_get_pseudo_bytes((void *)&zc
->zc_word
[ZIL_ZC_GUID_1
],
211 sizeof (zc
->zc_word
[ZIL_ZC_GUID_1
]));
212 zc
->zc_word
[ZIL_ZC_OBJSET
] = dmu_objset_id(zilog
->zl_os
);
213 zc
->zc_word
[ZIL_ZC_SEQ
] = 1ULL;
217 * Read a log block and make sure it's valid.
220 zil_read_log_block(zilog_t
*zilog
, boolean_t decrypt
, const blkptr_t
*bp
,
221 blkptr_t
*nbp
, void *dst
, char **end
)
223 enum zio_flag zio_flags
= ZIO_FLAG_CANFAIL
;
224 arc_flags_t aflags
= ARC_FLAG_WAIT
;
225 arc_buf_t
*abuf
= NULL
;
229 if (zilog
->zl_header
->zh_claim_txg
== 0)
230 zio_flags
|= ZIO_FLAG_SPECULATIVE
| ZIO_FLAG_SCRUB
;
232 if (!(zilog
->zl_header
->zh_flags
& ZIL_CLAIM_LR_SEQ_VALID
))
233 zio_flags
|= ZIO_FLAG_SPECULATIVE
;
236 zio_flags
|= ZIO_FLAG_RAW
;
238 SET_BOOKMARK(&zb
, bp
->blk_cksum
.zc_word
[ZIL_ZC_OBJSET
],
239 ZB_ZIL_OBJECT
, ZB_ZIL_LEVEL
, bp
->blk_cksum
.zc_word
[ZIL_ZC_SEQ
]);
241 error
= arc_read(NULL
, zilog
->zl_spa
, bp
, arc_getbuf_func
,
242 &abuf
, ZIO_PRIORITY_SYNC_READ
, zio_flags
, &aflags
, &zb
);
245 zio_cksum_t cksum
= bp
->blk_cksum
;
248 * Validate the checksummed log block.
250 * Sequence numbers should be... sequential. The checksum
251 * verifier for the next block should be bp's checksum plus 1.
253 * Also check the log chain linkage and size used.
255 cksum
.zc_word
[ZIL_ZC_SEQ
]++;
257 if (BP_GET_CHECKSUM(bp
) == ZIO_CHECKSUM_ZILOG2
) {
258 zil_chain_t
*zilc
= abuf
->b_data
;
259 char *lr
= (char *)(zilc
+ 1);
260 uint64_t len
= zilc
->zc_nused
- sizeof (zil_chain_t
);
262 if (memcmp(&cksum
, &zilc
->zc_next_blk
.blk_cksum
,
263 sizeof (cksum
)) || BP_IS_HOLE(&zilc
->zc_next_blk
)) {
264 error
= SET_ERROR(ECKSUM
);
266 ASSERT3U(len
, <=, SPA_OLD_MAXBLOCKSIZE
);
267 memcpy(dst
, lr
, len
);
268 *end
= (char *)dst
+ len
;
269 *nbp
= zilc
->zc_next_blk
;
272 char *lr
= abuf
->b_data
;
273 uint64_t size
= BP_GET_LSIZE(bp
);
274 zil_chain_t
*zilc
= (zil_chain_t
*)(lr
+ size
) - 1;
276 if (memcmp(&cksum
, &zilc
->zc_next_blk
.blk_cksum
,
277 sizeof (cksum
)) || BP_IS_HOLE(&zilc
->zc_next_blk
) ||
278 (zilc
->zc_nused
> (size
- sizeof (*zilc
)))) {
279 error
= SET_ERROR(ECKSUM
);
281 ASSERT3U(zilc
->zc_nused
, <=,
282 SPA_OLD_MAXBLOCKSIZE
);
283 memcpy(dst
, lr
, zilc
->zc_nused
);
284 *end
= (char *)dst
+ zilc
->zc_nused
;
285 *nbp
= zilc
->zc_next_blk
;
289 arc_buf_destroy(abuf
, &abuf
);
296 * Read a TX_WRITE log data block.
299 zil_read_log_data(zilog_t
*zilog
, const lr_write_t
*lr
, void *wbuf
)
301 enum zio_flag zio_flags
= ZIO_FLAG_CANFAIL
;
302 const blkptr_t
*bp
= &lr
->lr_blkptr
;
303 arc_flags_t aflags
= ARC_FLAG_WAIT
;
304 arc_buf_t
*abuf
= NULL
;
308 if (BP_IS_HOLE(bp
)) {
310 memset(wbuf
, 0, MAX(BP_GET_LSIZE(bp
), lr
->lr_length
));
314 if (zilog
->zl_header
->zh_claim_txg
== 0)
315 zio_flags
|= ZIO_FLAG_SPECULATIVE
| ZIO_FLAG_SCRUB
;
318 * If we are not using the resulting data, we are just checking that
319 * it hasn't been corrupted so we don't need to waste CPU time
320 * decompressing and decrypting it.
323 zio_flags
|= ZIO_FLAG_RAW
;
325 SET_BOOKMARK(&zb
, dmu_objset_id(zilog
->zl_os
), lr
->lr_foid
,
326 ZB_ZIL_LEVEL
, lr
->lr_offset
/ BP_GET_LSIZE(bp
));
328 error
= arc_read(NULL
, zilog
->zl_spa
, bp
, arc_getbuf_func
, &abuf
,
329 ZIO_PRIORITY_SYNC_READ
, zio_flags
, &aflags
, &zb
);
333 memcpy(wbuf
, abuf
->b_data
, arc_buf_size(abuf
));
334 arc_buf_destroy(abuf
, &abuf
);
341 * Parse the intent log, and call parse_func for each valid record within.
344 zil_parse(zilog_t
*zilog
, zil_parse_blk_func_t
*parse_blk_func
,
345 zil_parse_lr_func_t
*parse_lr_func
, void *arg
, uint64_t txg
,
348 const zil_header_t
*zh
= zilog
->zl_header
;
349 boolean_t claimed
= !!zh
->zh_claim_txg
;
350 uint64_t claim_blk_seq
= claimed
? zh
->zh_claim_blk_seq
: UINT64_MAX
;
351 uint64_t claim_lr_seq
= claimed
? zh
->zh_claim_lr_seq
: UINT64_MAX
;
352 uint64_t max_blk_seq
= 0;
353 uint64_t max_lr_seq
= 0;
354 uint64_t blk_count
= 0;
355 uint64_t lr_count
= 0;
356 blkptr_t blk
, next_blk
= {{{{0}}}};
361 * Old logs didn't record the maximum zh_claim_lr_seq.
363 if (!(zh
->zh_flags
& ZIL_CLAIM_LR_SEQ_VALID
))
364 claim_lr_seq
= UINT64_MAX
;
367 * Starting at the block pointed to by zh_log we read the log chain.
368 * For each block in the chain we strongly check that block to
369 * ensure its validity. We stop when an invalid block is found.
370 * For each block pointer in the chain we call parse_blk_func().
371 * For each record in each valid block we call parse_lr_func().
372 * If the log has been claimed, stop if we encounter a sequence
373 * number greater than the highest claimed sequence number.
375 lrbuf
= zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE
);
376 zil_bp_tree_init(zilog
);
378 for (blk
= zh
->zh_log
; !BP_IS_HOLE(&blk
); blk
= next_blk
) {
379 uint64_t blk_seq
= blk
.blk_cksum
.zc_word
[ZIL_ZC_SEQ
];
383 if (blk_seq
> claim_blk_seq
)
386 error
= parse_blk_func(zilog
, &blk
, arg
, txg
);
389 ASSERT3U(max_blk_seq
, <, blk_seq
);
390 max_blk_seq
= blk_seq
;
393 if (max_lr_seq
== claim_lr_seq
&& max_blk_seq
== claim_blk_seq
)
396 error
= zil_read_log_block(zilog
, decrypt
, &blk
, &next_blk
,
401 for (lrp
= lrbuf
; lrp
< end
; lrp
+= reclen
) {
402 lr_t
*lr
= (lr_t
*)lrp
;
403 reclen
= lr
->lrc_reclen
;
404 ASSERT3U(reclen
, >=, sizeof (lr_t
));
405 if (lr
->lrc_seq
> claim_lr_seq
)
408 error
= parse_lr_func(zilog
, lr
, arg
, txg
);
411 ASSERT3U(max_lr_seq
, <, lr
->lrc_seq
);
412 max_lr_seq
= lr
->lrc_seq
;
417 zilog
->zl_parse_error
= error
;
418 zilog
->zl_parse_blk_seq
= max_blk_seq
;
419 zilog
->zl_parse_lr_seq
= max_lr_seq
;
420 zilog
->zl_parse_blk_count
= blk_count
;
421 zilog
->zl_parse_lr_count
= lr_count
;
423 ASSERT(!claimed
|| !(zh
->zh_flags
& ZIL_CLAIM_LR_SEQ_VALID
) ||
424 (max_blk_seq
== claim_blk_seq
&& max_lr_seq
== claim_lr_seq
) ||
425 (decrypt
&& error
== EIO
));
427 zil_bp_tree_fini(zilog
);
428 zio_buf_free(lrbuf
, SPA_OLD_MAXBLOCKSIZE
);
434 zil_clear_log_block(zilog_t
*zilog
, const blkptr_t
*bp
, void *tx
,
438 ASSERT(!BP_IS_HOLE(bp
));
441 * As we call this function from the context of a rewind to a
442 * checkpoint, each ZIL block whose txg is later than the txg
443 * that we rewind to is invalid. Thus, we return -1 so
444 * zil_parse() doesn't attempt to read it.
446 if (bp
->blk_birth
>= first_txg
)
449 if (zil_bp_tree_add(zilog
, bp
) != 0)
452 zio_free(zilog
->zl_spa
, first_txg
, bp
);
457 zil_noop_log_record(zilog_t
*zilog
, const lr_t
*lrc
, void *tx
,
460 (void) zilog
, (void) lrc
, (void) tx
, (void) first_txg
;
465 zil_claim_log_block(zilog_t
*zilog
, const blkptr_t
*bp
, void *tx
,
469 * Claim log block if not already committed and not already claimed.
470 * If tx == NULL, just verify that the block is claimable.
472 if (BP_IS_HOLE(bp
) || bp
->blk_birth
< first_txg
||
473 zil_bp_tree_add(zilog
, bp
) != 0)
476 return (zio_wait(zio_claim(NULL
, zilog
->zl_spa
,
477 tx
== NULL
? 0 : first_txg
, bp
, spa_claim_notify
, NULL
,
478 ZIO_FLAG_CANFAIL
| ZIO_FLAG_SPECULATIVE
| ZIO_FLAG_SCRUB
)));
482 zil_claim_log_record(zilog_t
*zilog
, const lr_t
*lrc
, void *tx
,
485 lr_write_t
*lr
= (lr_write_t
*)lrc
;
488 if (lrc
->lrc_txtype
!= TX_WRITE
)
492 * If the block is not readable, don't claim it. This can happen
493 * in normal operation when a log block is written to disk before
494 * some of the dmu_sync() blocks it points to. In this case, the
495 * transaction cannot have been committed to anyone (we would have
496 * waited for all writes to be stable first), so it is semantically
497 * correct to declare this the end of the log.
499 if (lr
->lr_blkptr
.blk_birth
>= first_txg
) {
500 error
= zil_read_log_data(zilog
, lr
, NULL
);
505 return (zil_claim_log_block(zilog
, &lr
->lr_blkptr
, tx
, first_txg
));
509 zil_free_log_block(zilog_t
*zilog
, const blkptr_t
*bp
, void *tx
,
514 zio_free(zilog
->zl_spa
, dmu_tx_get_txg(tx
), bp
);
520 zil_free_log_record(zilog_t
*zilog
, const lr_t
*lrc
, void *tx
,
523 lr_write_t
*lr
= (lr_write_t
*)lrc
;
524 blkptr_t
*bp
= &lr
->lr_blkptr
;
527 * If we previously claimed it, we need to free it.
529 if (claim_txg
!= 0 && lrc
->lrc_txtype
== TX_WRITE
&&
530 bp
->blk_birth
>= claim_txg
&& zil_bp_tree_add(zilog
, bp
) == 0 &&
532 zio_free(zilog
->zl_spa
, dmu_tx_get_txg(tx
), bp
);
538 zil_lwb_vdev_compare(const void *x1
, const void *x2
)
540 const uint64_t v1
= ((zil_vdev_node_t
*)x1
)->zv_vdev
;
541 const uint64_t v2
= ((zil_vdev_node_t
*)x2
)->zv_vdev
;
543 return (TREE_CMP(v1
, v2
));
547 zil_alloc_lwb(zilog_t
*zilog
, blkptr_t
*bp
, boolean_t slog
, uint64_t txg
,
552 lwb
= kmem_cache_alloc(zil_lwb_cache
, KM_SLEEP
);
553 lwb
->lwb_zilog
= zilog
;
555 lwb
->lwb_fastwrite
= fastwrite
;
556 lwb
->lwb_slog
= slog
;
557 lwb
->lwb_state
= LWB_STATE_CLOSED
;
558 lwb
->lwb_buf
= zio_buf_alloc(BP_GET_LSIZE(bp
));
559 lwb
->lwb_max_txg
= txg
;
560 lwb
->lwb_write_zio
= NULL
;
561 lwb
->lwb_root_zio
= NULL
;
562 lwb
->lwb_issued_timestamp
= 0;
563 lwb
->lwb_issued_txg
= 0;
564 if (BP_GET_CHECKSUM(bp
) == ZIO_CHECKSUM_ZILOG2
) {
565 lwb
->lwb_nused
= sizeof (zil_chain_t
);
566 lwb
->lwb_sz
= BP_GET_LSIZE(bp
);
569 lwb
->lwb_sz
= BP_GET_LSIZE(bp
) - sizeof (zil_chain_t
);
572 mutex_enter(&zilog
->zl_lock
);
573 list_insert_tail(&zilog
->zl_lwb_list
, lwb
);
574 mutex_exit(&zilog
->zl_lock
);
576 ASSERT(!MUTEX_HELD(&lwb
->lwb_vdev_lock
));
577 ASSERT(avl_is_empty(&lwb
->lwb_vdev_tree
));
578 VERIFY(list_is_empty(&lwb
->lwb_waiters
));
579 VERIFY(list_is_empty(&lwb
->lwb_itxs
));
585 zil_free_lwb(zilog_t
*zilog
, lwb_t
*lwb
)
587 ASSERT(MUTEX_HELD(&zilog
->zl_lock
));
588 ASSERT(!MUTEX_HELD(&lwb
->lwb_vdev_lock
));
589 VERIFY(list_is_empty(&lwb
->lwb_waiters
));
590 VERIFY(list_is_empty(&lwb
->lwb_itxs
));
591 ASSERT(avl_is_empty(&lwb
->lwb_vdev_tree
));
592 ASSERT3P(lwb
->lwb_write_zio
, ==, NULL
);
593 ASSERT3P(lwb
->lwb_root_zio
, ==, NULL
);
594 ASSERT3U(lwb
->lwb_max_txg
, <=, spa_syncing_txg(zilog
->zl_spa
));
595 ASSERT(lwb
->lwb_state
== LWB_STATE_CLOSED
||
596 lwb
->lwb_state
== LWB_STATE_FLUSH_DONE
);
599 * Clear the zilog's field to indicate this lwb is no longer
600 * valid, and prevent use-after-free errors.
602 if (zilog
->zl_last_lwb_opened
== lwb
)
603 zilog
->zl_last_lwb_opened
= NULL
;
605 kmem_cache_free(zil_lwb_cache
, lwb
);
609 * Called when we create in-memory log transactions so that we know
610 * to cleanup the itxs at the end of spa_sync().
613 zilog_dirty(zilog_t
*zilog
, uint64_t txg
)
615 dsl_pool_t
*dp
= zilog
->zl_dmu_pool
;
616 dsl_dataset_t
*ds
= dmu_objset_ds(zilog
->zl_os
);
618 ASSERT(spa_writeable(zilog
->zl_spa
));
620 if (ds
->ds_is_snapshot
)
621 panic("dirtying snapshot!");
623 if (txg_list_add(&dp
->dp_dirty_zilogs
, zilog
, txg
)) {
624 /* up the hold count until we can be written out */
625 dmu_buf_add_ref(ds
->ds_dbuf
, zilog
);
627 zilog
->zl_dirty_max_txg
= MAX(txg
, zilog
->zl_dirty_max_txg
);
632 * Determine if the zil is dirty in the specified txg. Callers wanting to
633 * ensure that the dirty state does not change must hold the itxg_lock for
634 * the specified txg. Holding the lock will ensure that the zil cannot be
635 * dirtied (zil_itx_assign) or cleaned (zil_clean) while we check its current
638 static boolean_t __maybe_unused
639 zilog_is_dirty_in_txg(zilog_t
*zilog
, uint64_t txg
)
641 dsl_pool_t
*dp
= zilog
->zl_dmu_pool
;
643 if (txg_list_member(&dp
->dp_dirty_zilogs
, zilog
, txg
& TXG_MASK
))
649 * Determine if the zil is dirty. The zil is considered dirty if it has
650 * any pending itx records that have not been cleaned by zil_clean().
653 zilog_is_dirty(zilog_t
*zilog
)
655 dsl_pool_t
*dp
= zilog
->zl_dmu_pool
;
657 for (int t
= 0; t
< TXG_SIZE
; t
++) {
658 if (txg_list_member(&dp
->dp_dirty_zilogs
, zilog
, t
))
665 * Its called in zil_commit context (zil_process_commit_list()/zil_create()).
666 * It activates SPA_FEATURE_ZILSAXATTR feature, if its enabled.
667 * Check dsl_dataset_feature_is_active to avoid txg_wait_synced() on every
671 zil_commit_activate_saxattr_feature(zilog_t
*zilog
)
673 dsl_dataset_t
*ds
= dmu_objset_ds(zilog
->zl_os
);
677 if (spa_feature_is_enabled(zilog
->zl_spa
,
678 SPA_FEATURE_ZILSAXATTR
) &&
679 dmu_objset_type(zilog
->zl_os
) != DMU_OST_ZVOL
&&
680 !dsl_dataset_feature_is_active(ds
,
681 SPA_FEATURE_ZILSAXATTR
)) {
682 tx
= dmu_tx_create(zilog
->zl_os
);
683 VERIFY0(dmu_tx_assign(tx
, TXG_WAIT
));
684 dsl_dataset_dirty(ds
, tx
);
685 txg
= dmu_tx_get_txg(tx
);
687 mutex_enter(&ds
->ds_lock
);
688 ds
->ds_feature_activation
[SPA_FEATURE_ZILSAXATTR
] =
690 mutex_exit(&ds
->ds_lock
);
692 txg_wait_synced(zilog
->zl_dmu_pool
, txg
);
697 * Create an on-disk intent log.
700 zil_create(zilog_t
*zilog
)
702 const zil_header_t
*zh
= zilog
->zl_header
;
708 boolean_t fastwrite
= FALSE
;
709 boolean_t slog
= FALSE
;
710 dsl_dataset_t
*ds
= dmu_objset_ds(zilog
->zl_os
);
714 * Wait for any previous destroy to complete.
716 txg_wait_synced(zilog
->zl_dmu_pool
, zilog
->zl_destroy_txg
);
718 ASSERT(zh
->zh_claim_txg
== 0);
719 ASSERT(zh
->zh_replay_seq
== 0);
724 * Allocate an initial log block if:
725 * - there isn't one already
726 * - the existing block is the wrong endianness
728 if (BP_IS_HOLE(&blk
) || BP_SHOULD_BYTESWAP(&blk
)) {
729 tx
= dmu_tx_create(zilog
->zl_os
);
730 VERIFY0(dmu_tx_assign(tx
, TXG_WAIT
));
731 dsl_dataset_dirty(dmu_objset_ds(zilog
->zl_os
), tx
);
732 txg
= dmu_tx_get_txg(tx
);
734 if (!BP_IS_HOLE(&blk
)) {
735 zio_free(zilog
->zl_spa
, txg
, &blk
);
739 error
= zio_alloc_zil(zilog
->zl_spa
, zilog
->zl_os
, txg
, &blk
,
740 ZIL_MIN_BLKSZ
, &slog
);
744 zil_init_log_chain(zilog
, &blk
);
748 * Allocate a log write block (lwb) for the first log block.
751 lwb
= zil_alloc_lwb(zilog
, &blk
, slog
, txg
, fastwrite
);
754 * If we just allocated the first log block, commit our transaction
755 * and wait for zil_sync() to stuff the block pointer into zh_log.
756 * (zh is part of the MOS, so we cannot modify it in open context.)
760 * If "zilsaxattr" feature is enabled on zpool, then activate
761 * it now when we're creating the ZIL chain. We can't wait with
762 * this until we write the first xattr log record because we
763 * need to wait for the feature activation to sync out.
765 if (spa_feature_is_enabled(zilog
->zl_spa
,
766 SPA_FEATURE_ZILSAXATTR
) && dmu_objset_type(zilog
->zl_os
) !=
768 mutex_enter(&ds
->ds_lock
);
769 ds
->ds_feature_activation
[SPA_FEATURE_ZILSAXATTR
] =
771 mutex_exit(&ds
->ds_lock
);
775 txg_wait_synced(zilog
->zl_dmu_pool
, txg
);
778 * This branch covers the case where we enable the feature on a
779 * zpool that has existing ZIL headers.
781 zil_commit_activate_saxattr_feature(zilog
);
783 IMPLY(spa_feature_is_enabled(zilog
->zl_spa
, SPA_FEATURE_ZILSAXATTR
) &&
784 dmu_objset_type(zilog
->zl_os
) != DMU_OST_ZVOL
,
785 dsl_dataset_feature_is_active(ds
, SPA_FEATURE_ZILSAXATTR
));
787 ASSERT(error
!= 0 || memcmp(&blk
, &zh
->zh_log
, sizeof (blk
)) == 0);
788 IMPLY(error
== 0, lwb
!= NULL
);
794 * In one tx, free all log blocks and clear the log header. If keep_first
795 * is set, then we're replaying a log with no content. We want to keep the
796 * first block, however, so that the first synchronous transaction doesn't
797 * require a txg_wait_synced() in zil_create(). We don't need to
798 * txg_wait_synced() here either when keep_first is set, because both
799 * zil_create() and zil_destroy() will wait for any in-progress destroys
803 zil_destroy(zilog_t
*zilog
, boolean_t keep_first
)
805 const zil_header_t
*zh
= zilog
->zl_header
;
811 * Wait for any previous destroy to complete.
813 txg_wait_synced(zilog
->zl_dmu_pool
, zilog
->zl_destroy_txg
);
815 zilog
->zl_old_header
= *zh
; /* debugging aid */
817 if (BP_IS_HOLE(&zh
->zh_log
))
820 tx
= dmu_tx_create(zilog
->zl_os
);
821 VERIFY0(dmu_tx_assign(tx
, TXG_WAIT
));
822 dsl_dataset_dirty(dmu_objset_ds(zilog
->zl_os
), tx
);
823 txg
= dmu_tx_get_txg(tx
);
825 mutex_enter(&zilog
->zl_lock
);
827 ASSERT3U(zilog
->zl_destroy_txg
, <, txg
);
828 zilog
->zl_destroy_txg
= txg
;
829 zilog
->zl_keep_first
= keep_first
;
831 if (!list_is_empty(&zilog
->zl_lwb_list
)) {
832 ASSERT(zh
->zh_claim_txg
== 0);
834 while ((lwb
= list_head(&zilog
->zl_lwb_list
)) != NULL
) {
835 if (lwb
->lwb_fastwrite
)
836 metaslab_fastwrite_unmark(zilog
->zl_spa
,
839 list_remove(&zilog
->zl_lwb_list
, lwb
);
840 if (lwb
->lwb_buf
!= NULL
)
841 zio_buf_free(lwb
->lwb_buf
, lwb
->lwb_sz
);
842 zio_free(zilog
->zl_spa
, txg
, &lwb
->lwb_blk
);
843 zil_free_lwb(zilog
, lwb
);
845 } else if (!keep_first
) {
846 zil_destroy_sync(zilog
, tx
);
848 mutex_exit(&zilog
->zl_lock
);
854 zil_destroy_sync(zilog_t
*zilog
, dmu_tx_t
*tx
)
856 ASSERT(list_is_empty(&zilog
->zl_lwb_list
));
857 (void) zil_parse(zilog
, zil_free_log_block
,
858 zil_free_log_record
, tx
, zilog
->zl_header
->zh_claim_txg
, B_FALSE
);
862 zil_claim(dsl_pool_t
*dp
, dsl_dataset_t
*ds
, void *txarg
)
864 dmu_tx_t
*tx
= txarg
;
871 error
= dmu_objset_own_obj(dp
, ds
->ds_object
,
872 DMU_OST_ANY
, B_FALSE
, B_FALSE
, FTAG
, &os
);
875 * EBUSY indicates that the objset is inconsistent, in which
876 * case it can not have a ZIL.
878 if (error
!= EBUSY
) {
879 cmn_err(CE_WARN
, "can't open objset for %llu, error %u",
880 (unsigned long long)ds
->ds_object
, error
);
886 zilog
= dmu_objset_zil(os
);
887 zh
= zil_header_in_syncing_context(zilog
);
888 ASSERT3U(tx
->tx_txg
, ==, spa_first_txg(zilog
->zl_spa
));
889 first_txg
= spa_min_claim_txg(zilog
->zl_spa
);
892 * If the spa_log_state is not set to be cleared, check whether
893 * the current uberblock is a checkpoint one and if the current
894 * header has been claimed before moving on.
896 * If the current uberblock is a checkpointed uberblock then
897 * one of the following scenarios took place:
899 * 1] We are currently rewinding to the checkpoint of the pool.
900 * 2] We crashed in the middle of a checkpoint rewind but we
901 * did manage to write the checkpointed uberblock to the
902 * vdev labels, so when we tried to import the pool again
903 * the checkpointed uberblock was selected from the import
906 * In both cases we want to zero out all the ZIL blocks, except
907 * the ones that have been claimed at the time of the checkpoint
908 * (their zh_claim_txg != 0). The reason is that these blocks
909 * may be corrupted since we may have reused their locations on
910 * disk after we took the checkpoint.
912 * We could try to set spa_log_state to SPA_LOG_CLEAR earlier
913 * when we first figure out whether the current uberblock is
914 * checkpointed or not. Unfortunately, that would discard all
915 * the logs, including the ones that are claimed, and we would
918 if (spa_get_log_state(zilog
->zl_spa
) == SPA_LOG_CLEAR
||
919 (zilog
->zl_spa
->spa_uberblock
.ub_checkpoint_txg
!= 0 &&
920 zh
->zh_claim_txg
== 0)) {
921 if (!BP_IS_HOLE(&zh
->zh_log
)) {
922 (void) zil_parse(zilog
, zil_clear_log_block
,
923 zil_noop_log_record
, tx
, first_txg
, B_FALSE
);
925 BP_ZERO(&zh
->zh_log
);
926 if (os
->os_encrypted
)
927 os
->os_next_write_raw
[tx
->tx_txg
& TXG_MASK
] = B_TRUE
;
928 dsl_dataset_dirty(dmu_objset_ds(os
), tx
);
929 dmu_objset_disown(os
, B_FALSE
, FTAG
);
934 * If we are not rewinding and opening the pool normally, then
935 * the min_claim_txg should be equal to the first txg of the pool.
937 ASSERT3U(first_txg
, ==, spa_first_txg(zilog
->zl_spa
));
940 * Claim all log blocks if we haven't already done so, and remember
941 * the highest claimed sequence number. This ensures that if we can
942 * read only part of the log now (e.g. due to a missing device),
943 * but we can read the entire log later, we will not try to replay
944 * or destroy beyond the last block we successfully claimed.
946 ASSERT3U(zh
->zh_claim_txg
, <=, first_txg
);
947 if (zh
->zh_claim_txg
== 0 && !BP_IS_HOLE(&zh
->zh_log
)) {
948 (void) zil_parse(zilog
, zil_claim_log_block
,
949 zil_claim_log_record
, tx
, first_txg
, B_FALSE
);
950 zh
->zh_claim_txg
= first_txg
;
951 zh
->zh_claim_blk_seq
= zilog
->zl_parse_blk_seq
;
952 zh
->zh_claim_lr_seq
= zilog
->zl_parse_lr_seq
;
953 if (zilog
->zl_parse_lr_count
|| zilog
->zl_parse_blk_count
> 1)
954 zh
->zh_flags
|= ZIL_REPLAY_NEEDED
;
955 zh
->zh_flags
|= ZIL_CLAIM_LR_SEQ_VALID
;
956 if (os
->os_encrypted
)
957 os
->os_next_write_raw
[tx
->tx_txg
& TXG_MASK
] = B_TRUE
;
958 dsl_dataset_dirty(dmu_objset_ds(os
), tx
);
961 ASSERT3U(first_txg
, ==, (spa_last_synced_txg(zilog
->zl_spa
) + 1));
962 dmu_objset_disown(os
, B_FALSE
, FTAG
);
967 * Check the log by walking the log chain.
968 * Checksum errors are ok as they indicate the end of the chain.
969 * Any other error (no device or read failure) returns an error.
972 zil_check_log_chain(dsl_pool_t
*dp
, dsl_dataset_t
*ds
, void *tx
)
982 error
= dmu_objset_from_ds(ds
, &os
);
984 cmn_err(CE_WARN
, "can't open objset %llu, error %d",
985 (unsigned long long)ds
->ds_object
, error
);
989 zilog
= dmu_objset_zil(os
);
990 bp
= (blkptr_t
*)&zilog
->zl_header
->zh_log
;
992 if (!BP_IS_HOLE(bp
)) {
994 boolean_t valid
= B_TRUE
;
997 * Check the first block and determine if it's on a log device
998 * which may have been removed or faulted prior to loading this
999 * pool. If so, there's no point in checking the rest of the
1000 * log as its content should have already been synced to the
1003 spa_config_enter(os
->os_spa
, SCL_STATE
, FTAG
, RW_READER
);
1004 vd
= vdev_lookup_top(os
->os_spa
, DVA_GET_VDEV(&bp
->blk_dva
[0]));
1005 if (vd
->vdev_islog
&& vdev_is_dead(vd
))
1006 valid
= vdev_log_state_valid(vd
);
1007 spa_config_exit(os
->os_spa
, SCL_STATE
, FTAG
);
1013 * Check whether the current uberblock is checkpointed (e.g.
1014 * we are rewinding) and whether the current header has been
1015 * claimed or not. If it hasn't then skip verifying it. We
1016 * do this because its ZIL blocks may be part of the pool's
1017 * state before the rewind, which is no longer valid.
1019 zil_header_t
*zh
= zil_header_in_syncing_context(zilog
);
1020 if (zilog
->zl_spa
->spa_uberblock
.ub_checkpoint_txg
!= 0 &&
1021 zh
->zh_claim_txg
== 0)
1026 * Because tx == NULL, zil_claim_log_block() will not actually claim
1027 * any blocks, but just determine whether it is possible to do so.
1028 * In addition to checking the log chain, zil_claim_log_block()
1029 * will invoke zio_claim() with a done func of spa_claim_notify(),
1030 * which will update spa_max_claim_txg. See spa_load() for details.
1032 error
= zil_parse(zilog
, zil_claim_log_block
, zil_claim_log_record
, tx
,
1033 zilog
->zl_header
->zh_claim_txg
? -1ULL :
1034 spa_min_claim_txg(os
->os_spa
), B_FALSE
);
1036 return ((error
== ECKSUM
|| error
== ENOENT
) ? 0 : error
);
1040 * When an itx is "skipped", this function is used to properly mark the
1041 * waiter as "done, and signal any thread(s) waiting on it. An itx can
1042 * be skipped (and not committed to an lwb) for a variety of reasons,
1043 * one of them being that the itx was committed via spa_sync(), prior to
1044 * it being committed to an lwb; this can happen if a thread calling
1045 * zil_commit() is racing with spa_sync().
1048 zil_commit_waiter_skip(zil_commit_waiter_t
*zcw
)
1050 mutex_enter(&zcw
->zcw_lock
);
1051 ASSERT3B(zcw
->zcw_done
, ==, B_FALSE
);
1052 zcw
->zcw_done
= B_TRUE
;
1053 cv_broadcast(&zcw
->zcw_cv
);
1054 mutex_exit(&zcw
->zcw_lock
);
1058 * This function is used when the given waiter is to be linked into an
1059 * lwb's "lwb_waiter" list; i.e. when the itx is committed to the lwb.
1060 * At this point, the waiter will no longer be referenced by the itx,
1061 * and instead, will be referenced by the lwb.
1064 zil_commit_waiter_link_lwb(zil_commit_waiter_t
*zcw
, lwb_t
*lwb
)
1067 * The lwb_waiters field of the lwb is protected by the zilog's
1068 * zl_lock, thus it must be held when calling this function.
1070 ASSERT(MUTEX_HELD(&lwb
->lwb_zilog
->zl_lock
));
1072 mutex_enter(&zcw
->zcw_lock
);
1073 ASSERT(!list_link_active(&zcw
->zcw_node
));
1074 ASSERT3P(zcw
->zcw_lwb
, ==, NULL
);
1075 ASSERT3P(lwb
, !=, NULL
);
1076 ASSERT(lwb
->lwb_state
== LWB_STATE_OPENED
||
1077 lwb
->lwb_state
== LWB_STATE_ISSUED
||
1078 lwb
->lwb_state
== LWB_STATE_WRITE_DONE
);
1080 list_insert_tail(&lwb
->lwb_waiters
, zcw
);
1082 mutex_exit(&zcw
->zcw_lock
);
1086 * This function is used when zio_alloc_zil() fails to allocate a ZIL
1087 * block, and the given waiter must be linked to the "nolwb waiters"
1088 * list inside of zil_process_commit_list().
1091 zil_commit_waiter_link_nolwb(zil_commit_waiter_t
*zcw
, list_t
*nolwb
)
1093 mutex_enter(&zcw
->zcw_lock
);
1094 ASSERT(!list_link_active(&zcw
->zcw_node
));
1095 ASSERT3P(zcw
->zcw_lwb
, ==, NULL
);
1096 list_insert_tail(nolwb
, zcw
);
1097 mutex_exit(&zcw
->zcw_lock
);
1101 zil_lwb_add_block(lwb_t
*lwb
, const blkptr_t
*bp
)
1103 avl_tree_t
*t
= &lwb
->lwb_vdev_tree
;
1105 zil_vdev_node_t
*zv
, zvsearch
;
1106 int ndvas
= BP_GET_NDVAS(bp
);
1109 if (zil_nocacheflush
)
1112 mutex_enter(&lwb
->lwb_vdev_lock
);
1113 for (i
= 0; i
< ndvas
; i
++) {
1114 zvsearch
.zv_vdev
= DVA_GET_VDEV(&bp
->blk_dva
[i
]);
1115 if (avl_find(t
, &zvsearch
, &where
) == NULL
) {
1116 zv
= kmem_alloc(sizeof (*zv
), KM_SLEEP
);
1117 zv
->zv_vdev
= zvsearch
.zv_vdev
;
1118 avl_insert(t
, zv
, where
);
1121 mutex_exit(&lwb
->lwb_vdev_lock
);
1125 zil_lwb_flush_defer(lwb_t
*lwb
, lwb_t
*nlwb
)
1127 avl_tree_t
*src
= &lwb
->lwb_vdev_tree
;
1128 avl_tree_t
*dst
= &nlwb
->lwb_vdev_tree
;
1129 void *cookie
= NULL
;
1130 zil_vdev_node_t
*zv
;
1132 ASSERT3S(lwb
->lwb_state
, ==, LWB_STATE_WRITE_DONE
);
1133 ASSERT3S(nlwb
->lwb_state
, !=, LWB_STATE_WRITE_DONE
);
1134 ASSERT3S(nlwb
->lwb_state
, !=, LWB_STATE_FLUSH_DONE
);
1137 * While 'lwb' is at a point in its lifetime where lwb_vdev_tree does
1138 * not need the protection of lwb_vdev_lock (it will only be modified
1139 * while holding zilog->zl_lock) as its writes and those of its
1140 * children have all completed. The younger 'nlwb' may be waiting on
1141 * future writes to additional vdevs.
1143 mutex_enter(&nlwb
->lwb_vdev_lock
);
1145 * Tear down the 'lwb' vdev tree, ensuring that entries which do not
1146 * exist in 'nlwb' are moved to it, freeing any would-be duplicates.
1148 while ((zv
= avl_destroy_nodes(src
, &cookie
)) != NULL
) {
1151 if (avl_find(dst
, zv
, &where
) == NULL
) {
1152 avl_insert(dst
, zv
, where
);
1154 kmem_free(zv
, sizeof (*zv
));
1157 mutex_exit(&nlwb
->lwb_vdev_lock
);
1161 zil_lwb_add_txg(lwb_t
*lwb
, uint64_t txg
)
1163 lwb
->lwb_max_txg
= MAX(lwb
->lwb_max_txg
, txg
);
1167 * This function is a called after all vdevs associated with a given lwb
1168 * write have completed their DKIOCFLUSHWRITECACHE command; or as soon
1169 * as the lwb write completes, if "zil_nocacheflush" is set. Further,
1170 * all "previous" lwb's will have completed before this function is
1171 * called; i.e. this function is called for all previous lwbs before
1172 * it's called for "this" lwb (enforced via zio the dependencies
1173 * configured in zil_lwb_set_zio_dependency()).
1175 * The intention is for this function to be called as soon as the
1176 * contents of an lwb are considered "stable" on disk, and will survive
1177 * any sudden loss of power. At this point, any threads waiting for the
1178 * lwb to reach this state are signalled, and the "waiter" structures
1179 * are marked "done".
1182 zil_lwb_flush_vdevs_done(zio_t
*zio
)
1184 lwb_t
*lwb
= zio
->io_private
;
1185 zilog_t
*zilog
= lwb
->lwb_zilog
;
1186 zil_commit_waiter_t
*zcw
;
1190 spa_config_exit(zilog
->zl_spa
, SCL_STATE
, lwb
);
1192 zio_buf_free(lwb
->lwb_buf
, lwb
->lwb_sz
);
1194 mutex_enter(&zilog
->zl_lock
);
1197 * If we have had an allocation failure and the txg is
1198 * waiting to sync then we want zil_sync() to remove the lwb so
1199 * that it's not picked up as the next new one in
1200 * zil_process_commit_list(). zil_sync() will only remove the
1201 * lwb if lwb_buf is null.
1203 lwb
->lwb_buf
= NULL
;
1205 ASSERT3U(lwb
->lwb_issued_timestamp
, >, 0);
1206 zilog
->zl_last_lwb_latency
= gethrtime() - lwb
->lwb_issued_timestamp
;
1208 lwb
->lwb_root_zio
= NULL
;
1210 ASSERT3S(lwb
->lwb_state
, ==, LWB_STATE_WRITE_DONE
);
1211 lwb
->lwb_state
= LWB_STATE_FLUSH_DONE
;
1213 if (zilog
->zl_last_lwb_opened
== lwb
) {
1215 * Remember the highest committed log sequence number
1216 * for ztest. We only update this value when all the log
1217 * writes succeeded, because ztest wants to ASSERT that
1218 * it got the whole log chain.
1220 zilog
->zl_commit_lr_seq
= zilog
->zl_lr_seq
;
1223 while ((itx
= list_head(&lwb
->lwb_itxs
)) != NULL
) {
1224 list_remove(&lwb
->lwb_itxs
, itx
);
1225 zil_itx_destroy(itx
);
1228 while ((zcw
= list_head(&lwb
->lwb_waiters
)) != NULL
) {
1229 mutex_enter(&zcw
->zcw_lock
);
1231 ASSERT(list_link_active(&zcw
->zcw_node
));
1232 list_remove(&lwb
->lwb_waiters
, zcw
);
1234 ASSERT3P(zcw
->zcw_lwb
, ==, lwb
);
1235 zcw
->zcw_lwb
= NULL
;
1237 * We expect any ZIO errors from child ZIOs to have been
1238 * propagated "up" to this specific LWB's root ZIO, in
1239 * order for this error handling to work correctly. This
1240 * includes ZIO errors from either this LWB's write or
1241 * flush, as well as any errors from other dependent LWBs
1242 * (e.g. a root LWB ZIO that might be a child of this LWB).
1244 * With that said, it's important to note that LWB flush
1245 * errors are not propagated up to the LWB root ZIO.
1246 * This is incorrect behavior, and results in VDEV flush
1247 * errors not being handled correctly here. See the
1248 * comment above the call to "zio_flush" for details.
1251 zcw
->zcw_zio_error
= zio
->io_error
;
1253 ASSERT3B(zcw
->zcw_done
, ==, B_FALSE
);
1254 zcw
->zcw_done
= B_TRUE
;
1255 cv_broadcast(&zcw
->zcw_cv
);
1257 mutex_exit(&zcw
->zcw_lock
);
1260 mutex_exit(&zilog
->zl_lock
);
1262 mutex_enter(&zilog
->zl_lwb_io_lock
);
1263 txg
= lwb
->lwb_issued_txg
;
1264 ASSERT3U(zilog
->zl_lwb_inflight
[txg
& TXG_MASK
], >, 0);
1265 zilog
->zl_lwb_inflight
[txg
& TXG_MASK
]--;
1266 if (zilog
->zl_lwb_inflight
[txg
& TXG_MASK
] == 0)
1267 cv_broadcast(&zilog
->zl_lwb_io_cv
);
1268 mutex_exit(&zilog
->zl_lwb_io_lock
);
1272 * Wait for the completion of all issued write/flush of that txg provided.
1273 * It guarantees zil_lwb_flush_vdevs_done() is called and returned.
1276 zil_lwb_flush_wait_all(zilog_t
*zilog
, uint64_t txg
)
1278 ASSERT3U(txg
, ==, spa_syncing_txg(zilog
->zl_spa
));
1280 mutex_enter(&zilog
->zl_lwb_io_lock
);
1281 while (zilog
->zl_lwb_inflight
[txg
& TXG_MASK
] > 0)
1282 cv_wait(&zilog
->zl_lwb_io_cv
, &zilog
->zl_lwb_io_lock
);
1283 mutex_exit(&zilog
->zl_lwb_io_lock
);
1286 mutex_enter(&zilog
->zl_lock
);
1287 mutex_enter(&zilog
->zl_lwb_io_lock
);
1288 lwb_t
*lwb
= list_head(&zilog
->zl_lwb_list
);
1289 while (lwb
!= NULL
&& lwb
->lwb_max_txg
<= txg
) {
1290 if (lwb
->lwb_issued_txg
<= txg
) {
1291 ASSERT(lwb
->lwb_state
!= LWB_STATE_ISSUED
);
1292 ASSERT(lwb
->lwb_state
!= LWB_STATE_WRITE_DONE
);
1293 IMPLY(lwb
->lwb_issued_txg
> 0,
1294 lwb
->lwb_state
== LWB_STATE_FLUSH_DONE
);
1296 IMPLY(lwb
->lwb_state
== LWB_STATE_FLUSH_DONE
,
1297 lwb
->lwb_buf
== NULL
);
1298 lwb
= list_next(&zilog
->zl_lwb_list
, lwb
);
1300 mutex_exit(&zilog
->zl_lwb_io_lock
);
1301 mutex_exit(&zilog
->zl_lock
);
1306 * This is called when an lwb's write zio completes. The callback's
1307 * purpose is to issue the DKIOCFLUSHWRITECACHE commands for the vdevs
1308 * in the lwb's lwb_vdev_tree. The tree will contain the vdevs involved
1309 * in writing out this specific lwb's data, and in the case that cache
1310 * flushes have been deferred, vdevs involved in writing the data for
1311 * previous lwbs. The writes corresponding to all the vdevs in the
1312 * lwb_vdev_tree will have completed by the time this is called, due to
1313 * the zio dependencies configured in zil_lwb_set_zio_dependency(),
1314 * which takes deferred flushes into account. The lwb will be "done"
1315 * once zil_lwb_flush_vdevs_done() is called, which occurs in the zio
1316 * completion callback for the lwb's root zio.
1319 zil_lwb_write_done(zio_t
*zio
)
1321 lwb_t
*lwb
= zio
->io_private
;
1322 spa_t
*spa
= zio
->io_spa
;
1323 zilog_t
*zilog
= lwb
->lwb_zilog
;
1324 avl_tree_t
*t
= &lwb
->lwb_vdev_tree
;
1325 void *cookie
= NULL
;
1326 zil_vdev_node_t
*zv
;
1329 ASSERT3S(spa_config_held(spa
, SCL_STATE
, RW_READER
), !=, 0);
1331 ASSERT(BP_GET_COMPRESS(zio
->io_bp
) == ZIO_COMPRESS_OFF
);
1332 ASSERT(BP_GET_TYPE(zio
->io_bp
) == DMU_OT_INTENT_LOG
);
1333 ASSERT(BP_GET_LEVEL(zio
->io_bp
) == 0);
1334 ASSERT(BP_GET_BYTEORDER(zio
->io_bp
) == ZFS_HOST_BYTEORDER
);
1335 ASSERT(!BP_IS_GANG(zio
->io_bp
));
1336 ASSERT(!BP_IS_HOLE(zio
->io_bp
));
1337 ASSERT(BP_GET_FILL(zio
->io_bp
) == 0);
1339 abd_free(zio
->io_abd
);
1341 mutex_enter(&zilog
->zl_lock
);
1342 ASSERT3S(lwb
->lwb_state
, ==, LWB_STATE_ISSUED
);
1343 lwb
->lwb_state
= LWB_STATE_WRITE_DONE
;
1344 lwb
->lwb_write_zio
= NULL
;
1345 lwb
->lwb_fastwrite
= FALSE
;
1346 nlwb
= list_next(&zilog
->zl_lwb_list
, lwb
);
1347 mutex_exit(&zilog
->zl_lock
);
1349 if (avl_numnodes(t
) == 0)
1353 * If there was an IO error, we're not going to call zio_flush()
1354 * on these vdevs, so we simply empty the tree and free the
1355 * nodes. We avoid calling zio_flush() since there isn't any
1356 * good reason for doing so, after the lwb block failed to be
1359 * Additionally, we don't perform any further error handling at
1360 * this point (e.g. setting "zcw_zio_error" appropriately), as
1361 * we expect that to occur in "zil_lwb_flush_vdevs_done" (thus,
1362 * we expect any error seen here, to have been propagated to
1365 if (zio
->io_error
!= 0) {
1366 while ((zv
= avl_destroy_nodes(t
, &cookie
)) != NULL
)
1367 kmem_free(zv
, sizeof (*zv
));
1372 * If this lwb does not have any threads waiting for it to
1373 * complete, we want to defer issuing the DKIOCFLUSHWRITECACHE
1374 * command to the vdevs written to by "this" lwb, and instead
1375 * rely on the "next" lwb to handle the DKIOCFLUSHWRITECACHE
1376 * command for those vdevs. Thus, we merge the vdev tree of
1377 * "this" lwb with the vdev tree of the "next" lwb in the list,
1378 * and assume the "next" lwb will handle flushing the vdevs (or
1379 * deferring the flush(s) again).
1381 * This is a useful performance optimization, especially for
1382 * workloads with lots of async write activity and few sync
1383 * write and/or fsync activity, as it has the potential to
1384 * coalesce multiple flush commands to a vdev into one.
1386 if (list_head(&lwb
->lwb_waiters
) == NULL
&& nlwb
!= NULL
) {
1387 zil_lwb_flush_defer(lwb
, nlwb
);
1388 ASSERT(avl_is_empty(&lwb
->lwb_vdev_tree
));
1392 while ((zv
= avl_destroy_nodes(t
, &cookie
)) != NULL
) {
1393 vdev_t
*vd
= vdev_lookup_top(spa
, zv
->zv_vdev
);
1396 * The "ZIO_FLAG_DONT_PROPAGATE" is currently
1397 * always used within "zio_flush". This means,
1398 * any errors when flushing the vdev(s), will
1399 * (unfortunately) not be handled correctly,
1400 * since these "zio_flush" errors will not be
1401 * propagated up to "zil_lwb_flush_vdevs_done".
1403 zio_flush(lwb
->lwb_root_zio
, vd
);
1405 kmem_free(zv
, sizeof (*zv
));
1410 zil_lwb_set_zio_dependency(zilog_t
*zilog
, lwb_t
*lwb
)
1412 lwb_t
*last_lwb_opened
= zilog
->zl_last_lwb_opened
;
1414 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
1415 ASSERT(MUTEX_HELD(&zilog
->zl_lock
));
1418 * The zilog's "zl_last_lwb_opened" field is used to build the
1419 * lwb/zio dependency chain, which is used to preserve the
1420 * ordering of lwb completions that is required by the semantics
1421 * of the ZIL. Each new lwb zio becomes a parent of the
1422 * "previous" lwb zio, such that the new lwb's zio cannot
1423 * complete until the "previous" lwb's zio completes.
1425 * This is required by the semantics of zil_commit(); the commit
1426 * waiters attached to the lwbs will be woken in the lwb zio's
1427 * completion callback, so this zio dependency graph ensures the
1428 * waiters are woken in the correct order (the same order the
1429 * lwbs were created).
1431 if (last_lwb_opened
!= NULL
&&
1432 last_lwb_opened
->lwb_state
!= LWB_STATE_FLUSH_DONE
) {
1433 ASSERT(last_lwb_opened
->lwb_state
== LWB_STATE_OPENED
||
1434 last_lwb_opened
->lwb_state
== LWB_STATE_ISSUED
||
1435 last_lwb_opened
->lwb_state
== LWB_STATE_WRITE_DONE
);
1437 ASSERT3P(last_lwb_opened
->lwb_root_zio
, !=, NULL
);
1438 zio_add_child(lwb
->lwb_root_zio
,
1439 last_lwb_opened
->lwb_root_zio
);
1442 * If the previous lwb's write hasn't already completed,
1443 * we also want to order the completion of the lwb write
1444 * zios (above, we only order the completion of the lwb
1445 * root zios). This is required because of how we can
1446 * defer the DKIOCFLUSHWRITECACHE commands for each lwb.
1448 * When the DKIOCFLUSHWRITECACHE commands are deferred,
1449 * the previous lwb will rely on this lwb to flush the
1450 * vdevs written to by that previous lwb. Thus, we need
1451 * to ensure this lwb doesn't issue the flush until
1452 * after the previous lwb's write completes. We ensure
1453 * this ordering by setting the zio parent/child
1454 * relationship here.
1456 * Without this relationship on the lwb's write zio,
1457 * it's possible for this lwb's write to complete prior
1458 * to the previous lwb's write completing; and thus, the
1459 * vdevs for the previous lwb would be flushed prior to
1460 * that lwb's data being written to those vdevs (the
1461 * vdevs are flushed in the lwb write zio's completion
1462 * handler, zil_lwb_write_done()).
1464 if (last_lwb_opened
->lwb_state
!= LWB_STATE_WRITE_DONE
) {
1465 ASSERT(last_lwb_opened
->lwb_state
== LWB_STATE_OPENED
||
1466 last_lwb_opened
->lwb_state
== LWB_STATE_ISSUED
);
1468 ASSERT3P(last_lwb_opened
->lwb_write_zio
, !=, NULL
);
1469 zio_add_child(lwb
->lwb_write_zio
,
1470 last_lwb_opened
->lwb_write_zio
);
1477 * This function's purpose is to "open" an lwb such that it is ready to
1478 * accept new itxs being committed to it. To do this, the lwb's zio
1479 * structures are created, and linked to the lwb. This function is
1480 * idempotent; if the passed in lwb has already been opened, this
1481 * function is essentially a no-op.
1484 zil_lwb_write_open(zilog_t
*zilog
, lwb_t
*lwb
)
1486 zbookmark_phys_t zb
;
1487 zio_priority_t prio
;
1489 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
1490 ASSERT3P(lwb
, !=, NULL
);
1491 EQUIV(lwb
->lwb_root_zio
== NULL
, lwb
->lwb_state
== LWB_STATE_CLOSED
);
1492 EQUIV(lwb
->lwb_root_zio
!= NULL
, lwb
->lwb_state
== LWB_STATE_OPENED
);
1494 SET_BOOKMARK(&zb
, lwb
->lwb_blk
.blk_cksum
.zc_word
[ZIL_ZC_OBJSET
],
1495 ZB_ZIL_OBJECT
, ZB_ZIL_LEVEL
,
1496 lwb
->lwb_blk
.blk_cksum
.zc_word
[ZIL_ZC_SEQ
]);
1498 /* Lock so zil_sync() doesn't fastwrite_unmark after zio is created */
1499 mutex_enter(&zilog
->zl_lock
);
1500 if (lwb
->lwb_root_zio
== NULL
) {
1501 abd_t
*lwb_abd
= abd_get_from_buf(lwb
->lwb_buf
,
1502 BP_GET_LSIZE(&lwb
->lwb_blk
));
1504 if (!lwb
->lwb_fastwrite
) {
1505 metaslab_fastwrite_mark(zilog
->zl_spa
, &lwb
->lwb_blk
);
1506 lwb
->lwb_fastwrite
= 1;
1509 if (!lwb
->lwb_slog
|| zilog
->zl_cur_used
<= zil_slog_bulk
)
1510 prio
= ZIO_PRIORITY_SYNC_WRITE
;
1512 prio
= ZIO_PRIORITY_ASYNC_WRITE
;
1514 lwb
->lwb_root_zio
= zio_root(zilog
->zl_spa
,
1515 zil_lwb_flush_vdevs_done
, lwb
, ZIO_FLAG_CANFAIL
);
1516 ASSERT3P(lwb
->lwb_root_zio
, !=, NULL
);
1518 lwb
->lwb_write_zio
= zio_rewrite(lwb
->lwb_root_zio
,
1519 zilog
->zl_spa
, 0, &lwb
->lwb_blk
, lwb_abd
,
1520 BP_GET_LSIZE(&lwb
->lwb_blk
), zil_lwb_write_done
, lwb
,
1521 prio
, ZIO_FLAG_CANFAIL
| ZIO_FLAG_FASTWRITE
, &zb
);
1522 ASSERT3P(lwb
->lwb_write_zio
, !=, NULL
);
1524 lwb
->lwb_state
= LWB_STATE_OPENED
;
1526 zil_lwb_set_zio_dependency(zilog
, lwb
);
1527 zilog
->zl_last_lwb_opened
= lwb
;
1529 mutex_exit(&zilog
->zl_lock
);
1531 ASSERT3P(lwb
->lwb_root_zio
, !=, NULL
);
1532 ASSERT3P(lwb
->lwb_write_zio
, !=, NULL
);
1533 ASSERT3S(lwb
->lwb_state
, ==, LWB_STATE_OPENED
);
1537 * Define a limited set of intent log block sizes.
1539 * These must be a multiple of 4KB. Note only the amount used (again
1540 * aligned to 4KB) actually gets written. However, we can't always just
1541 * allocate SPA_OLD_MAXBLOCKSIZE as the slog space could be exhausted.
1543 static const struct {
1546 } zil_block_buckets
[] = {
1547 { 4096, 4096 }, /* non TX_WRITE */
1548 { 8192 + 4096, 8192 + 4096 }, /* database */
1549 { 32768 + 4096, 32768 + 4096 }, /* NFS writes */
1550 { 65536 + 4096, 65536 + 4096 }, /* 64KB writes */
1551 { 131072, 131072 }, /* < 128KB writes */
1552 { 131072 +4096, 65536 + 4096 }, /* 128KB writes */
1553 { UINT64_MAX
, SPA_OLD_MAXBLOCKSIZE
}, /* > 128KB writes */
1557 * Maximum block size used by the ZIL. This is picked up when the ZIL is
1558 * initialized. Otherwise this should not be used directly; see
1559 * zl_max_block_size instead.
1561 static int zil_maxblocksize
= SPA_OLD_MAXBLOCKSIZE
;
1564 * Start a log block write and advance to the next log block.
1565 * Calls are serialized.
1568 zil_lwb_write_issue(zilog_t
*zilog
, lwb_t
*lwb
)
1572 spa_t
*spa
= zilog
->zl_spa
;
1576 uint64_t zil_blksz
, wsz
;
1580 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
1581 ASSERT3P(lwb
->lwb_root_zio
, !=, NULL
);
1582 ASSERT3P(lwb
->lwb_write_zio
, !=, NULL
);
1583 ASSERT3S(lwb
->lwb_state
, ==, LWB_STATE_OPENED
);
1585 if (BP_GET_CHECKSUM(&lwb
->lwb_blk
) == ZIO_CHECKSUM_ZILOG2
) {
1586 zilc
= (zil_chain_t
*)lwb
->lwb_buf
;
1587 bp
= &zilc
->zc_next_blk
;
1589 zilc
= (zil_chain_t
*)(lwb
->lwb_buf
+ lwb
->lwb_sz
);
1590 bp
= &zilc
->zc_next_blk
;
1593 ASSERT(lwb
->lwb_nused
<= lwb
->lwb_sz
);
1596 * Allocate the next block and save its address in this block
1597 * before writing it in order to establish the log chain.
1600 tx
= dmu_tx_create(zilog
->zl_os
);
1603 * Since we are not going to create any new dirty data, and we
1604 * can even help with clearing the existing dirty data, we
1605 * should not be subject to the dirty data based delays. We
1606 * use TXG_NOTHROTTLE to bypass the delay mechanism.
1608 VERIFY0(dmu_tx_assign(tx
, TXG_WAIT
| TXG_NOTHROTTLE
));
1610 dsl_dataset_dirty(dmu_objset_ds(zilog
->zl_os
), tx
);
1611 txg
= dmu_tx_get_txg(tx
);
1613 mutex_enter(&zilog
->zl_lwb_io_lock
);
1614 lwb
->lwb_issued_txg
= txg
;
1615 zilog
->zl_lwb_inflight
[txg
& TXG_MASK
]++;
1616 zilog
->zl_lwb_max_issued_txg
= MAX(txg
, zilog
->zl_lwb_max_issued_txg
);
1617 mutex_exit(&zilog
->zl_lwb_io_lock
);
1620 * Log blocks are pre-allocated. Here we select the size of the next
1621 * block, based on size used in the last block.
1622 * - first find the smallest bucket that will fit the block from a
1623 * limited set of block sizes. This is because it's faster to write
1624 * blocks allocated from the same metaslab as they are adjacent or
1626 * - next find the maximum from the new suggested size and an array of
1627 * previous sizes. This lessens a picket fence effect of wrongly
1628 * guessing the size if we have a stream of say 2k, 64k, 2k, 64k
1631 * Note we only write what is used, but we can't just allocate
1632 * the maximum block size because we can exhaust the available
1635 zil_blksz
= zilog
->zl_cur_used
+ sizeof (zil_chain_t
);
1636 for (i
= 0; zil_blksz
> zil_block_buckets
[i
].limit
; i
++)
1638 zil_blksz
= MIN(zil_block_buckets
[i
].blksz
, zilog
->zl_max_block_size
);
1639 zilog
->zl_prev_blks
[zilog
->zl_prev_rotor
] = zil_blksz
;
1640 for (i
= 0; i
< ZIL_PREV_BLKS
; i
++)
1641 zil_blksz
= MAX(zil_blksz
, zilog
->zl_prev_blks
[i
]);
1642 zilog
->zl_prev_rotor
= (zilog
->zl_prev_rotor
+ 1) & (ZIL_PREV_BLKS
- 1);
1645 error
= zio_alloc_zil(spa
, zilog
->zl_os
, txg
, bp
, zil_blksz
, &slog
);
1647 ZIL_STAT_BUMP(zil_itx_metaslab_slog_count
);
1648 ZIL_STAT_INCR(zil_itx_metaslab_slog_bytes
, lwb
->lwb_nused
);
1650 ZIL_STAT_BUMP(zil_itx_metaslab_normal_count
);
1651 ZIL_STAT_INCR(zil_itx_metaslab_normal_bytes
, lwb
->lwb_nused
);
1654 ASSERT3U(bp
->blk_birth
, ==, txg
);
1655 bp
->blk_cksum
= lwb
->lwb_blk
.blk_cksum
;
1656 bp
->blk_cksum
.zc_word
[ZIL_ZC_SEQ
]++;
1659 * Allocate a new log write block (lwb).
1661 nlwb
= zil_alloc_lwb(zilog
, bp
, slog
, txg
, TRUE
);
1664 if (BP_GET_CHECKSUM(&lwb
->lwb_blk
) == ZIO_CHECKSUM_ZILOG2
) {
1665 /* For Slim ZIL only write what is used. */
1666 wsz
= P2ROUNDUP_TYPED(lwb
->lwb_nused
, ZIL_MIN_BLKSZ
, uint64_t);
1667 ASSERT3U(wsz
, <=, lwb
->lwb_sz
);
1668 zio_shrink(lwb
->lwb_write_zio
, wsz
);
1675 zilc
->zc_nused
= lwb
->lwb_nused
;
1676 zilc
->zc_eck
.zec_cksum
= lwb
->lwb_blk
.blk_cksum
;
1679 * clear unused data for security
1681 memset(lwb
->lwb_buf
+ lwb
->lwb_nused
, 0, wsz
- lwb
->lwb_nused
);
1683 spa_config_enter(zilog
->zl_spa
, SCL_STATE
, lwb
, RW_READER
);
1685 zil_lwb_add_block(lwb
, &lwb
->lwb_blk
);
1686 lwb
->lwb_issued_timestamp
= gethrtime();
1687 lwb
->lwb_state
= LWB_STATE_ISSUED
;
1689 zio_nowait(lwb
->lwb_root_zio
);
1690 zio_nowait(lwb
->lwb_write_zio
);
1695 * If there was an allocation failure then nlwb will be null which
1696 * forces a txg_wait_synced().
1702 * Maximum amount of write data that can be put into single log block.
1705 zil_max_log_data(zilog_t
*zilog
)
1707 return (zilog
->zl_max_block_size
-
1708 sizeof (zil_chain_t
) - sizeof (lr_write_t
));
1712 * Maximum amount of log space we agree to waste to reduce number of
1713 * WR_NEED_COPY chunks to reduce zl_get_data() overhead (~12%).
1715 static inline uint64_t
1716 zil_max_waste_space(zilog_t
*zilog
)
1718 return (zil_max_log_data(zilog
) / 8);
1722 * Maximum amount of write data for WR_COPIED. For correctness, consumers
1723 * must fall back to WR_NEED_COPY if we can't fit the entire record into one
1724 * maximum sized log block, because each WR_COPIED record must fit in a
1725 * single log block. For space efficiency, we want to fit two records into a
1726 * max-sized log block.
1729 zil_max_copied_data(zilog_t
*zilog
)
1731 return ((zilog
->zl_max_block_size
- sizeof (zil_chain_t
)) / 2 -
1732 sizeof (lr_write_t
));
1736 zil_lwb_commit(zilog_t
*zilog
, itx_t
*itx
, lwb_t
*lwb
)
1739 lr_write_t
*lrwb
, *lrw
;
1741 uint64_t dlen
, dnow
, dpad
, lwb_sp
, reclen
, txg
, max_log_data
;
1743 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
1744 ASSERT3P(lwb
, !=, NULL
);
1745 ASSERT3P(lwb
->lwb_buf
, !=, NULL
);
1747 zil_lwb_write_open(zilog
, lwb
);
1750 lrw
= (lr_write_t
*)lrc
;
1753 * A commit itx doesn't represent any on-disk state; instead
1754 * it's simply used as a place holder on the commit list, and
1755 * provides a mechanism for attaching a "commit waiter" onto the
1756 * correct lwb (such that the waiter can be signalled upon
1757 * completion of that lwb). Thus, we don't process this itx's
1758 * log record if it's a commit itx (these itx's don't have log
1759 * records), and instead link the itx's waiter onto the lwb's
1762 * For more details, see the comment above zil_commit().
1764 if (lrc
->lrc_txtype
== TX_COMMIT
) {
1765 mutex_enter(&zilog
->zl_lock
);
1766 zil_commit_waiter_link_lwb(itx
->itx_private
, lwb
);
1767 itx
->itx_private
= NULL
;
1768 mutex_exit(&zilog
->zl_lock
);
1772 if (lrc
->lrc_txtype
== TX_WRITE
&& itx
->itx_wr_state
== WR_NEED_COPY
) {
1773 dlen
= P2ROUNDUP_TYPED(
1774 lrw
->lr_length
, sizeof (uint64_t), uint64_t);
1775 dpad
= dlen
- lrw
->lr_length
;
1779 reclen
= lrc
->lrc_reclen
;
1780 zilog
->zl_cur_used
+= (reclen
+ dlen
);
1783 ASSERT3U(zilog
->zl_cur_used
, <, UINT64_MAX
- (reclen
+ dlen
));
1787 * If this record won't fit in the current log block, start a new one.
1788 * For WR_NEED_COPY optimize layout for minimal number of chunks.
1790 lwb_sp
= lwb
->lwb_sz
- lwb
->lwb_nused
;
1791 max_log_data
= zil_max_log_data(zilog
);
1792 if (reclen
> lwb_sp
|| (reclen
+ dlen
> lwb_sp
&&
1793 lwb_sp
< zil_max_waste_space(zilog
) &&
1794 (dlen
% max_log_data
== 0 ||
1795 lwb_sp
< reclen
+ dlen
% max_log_data
))) {
1796 lwb
= zil_lwb_write_issue(zilog
, lwb
);
1799 zil_lwb_write_open(zilog
, lwb
);
1800 ASSERT(LWB_EMPTY(lwb
));
1801 lwb_sp
= lwb
->lwb_sz
- lwb
->lwb_nused
;
1804 * There must be enough space in the new, empty log block to
1805 * hold reclen. For WR_COPIED, we need to fit the whole
1806 * record in one block, and reclen is the header size + the
1807 * data size. For WR_NEED_COPY, we can create multiple
1808 * records, splitting the data into multiple blocks, so we
1809 * only need to fit one word of data per block; in this case
1810 * reclen is just the header size (no data).
1812 ASSERT3U(reclen
+ MIN(dlen
, sizeof (uint64_t)), <=, lwb_sp
);
1815 dnow
= MIN(dlen
, lwb_sp
- reclen
);
1816 lr_buf
= lwb
->lwb_buf
+ lwb
->lwb_nused
;
1817 memcpy(lr_buf
, lrc
, reclen
);
1818 lrcb
= (lr_t
*)lr_buf
; /* Like lrc, but inside lwb. */
1819 lrwb
= (lr_write_t
*)lrcb
; /* Like lrw, but inside lwb. */
1821 ZIL_STAT_BUMP(zil_itx_count
);
1824 * If it's a write, fetch the data or get its blkptr as appropriate.
1826 if (lrc
->lrc_txtype
== TX_WRITE
) {
1827 if (txg
> spa_freeze_txg(zilog
->zl_spa
))
1828 txg_wait_synced(zilog
->zl_dmu_pool
, txg
);
1829 if (itx
->itx_wr_state
== WR_COPIED
) {
1830 ZIL_STAT_BUMP(zil_itx_copied_count
);
1831 ZIL_STAT_INCR(zil_itx_copied_bytes
, lrw
->lr_length
);
1836 if (itx
->itx_wr_state
== WR_NEED_COPY
) {
1837 dbuf
= lr_buf
+ reclen
;
1838 lrcb
->lrc_reclen
+= dnow
;
1839 if (lrwb
->lr_length
> dnow
)
1840 lrwb
->lr_length
= dnow
;
1841 lrw
->lr_offset
+= dnow
;
1842 lrw
->lr_length
-= dnow
;
1843 ZIL_STAT_BUMP(zil_itx_needcopy_count
);
1844 ZIL_STAT_INCR(zil_itx_needcopy_bytes
, dnow
);
1846 ASSERT3S(itx
->itx_wr_state
, ==, WR_INDIRECT
);
1848 ZIL_STAT_BUMP(zil_itx_indirect_count
);
1849 ZIL_STAT_INCR(zil_itx_indirect_bytes
,
1854 * We pass in the "lwb_write_zio" rather than
1855 * "lwb_root_zio" so that the "lwb_write_zio"
1856 * becomes the parent of any zio's created by
1857 * the "zl_get_data" callback. The vdevs are
1858 * flushed after the "lwb_write_zio" completes,
1859 * so we want to make sure that completion
1860 * callback waits for these additional zio's,
1861 * such that the vdevs used by those zio's will
1862 * be included in the lwb's vdev tree, and those
1863 * vdevs will be properly flushed. If we passed
1864 * in "lwb_root_zio" here, then these additional
1865 * vdevs may not be flushed; e.g. if these zio's
1866 * completed after "lwb_write_zio" completed.
1868 error
= zilog
->zl_get_data(itx
->itx_private
,
1869 itx
->itx_gen
, lrwb
, dbuf
, lwb
,
1870 lwb
->lwb_write_zio
);
1871 if (dbuf
!= NULL
&& error
== 0 && dnow
== dlen
)
1872 /* Zero any padding bytes in the last block. */
1873 memset((char *)dbuf
+ lrwb
->lr_length
, 0, dpad
);
1876 txg_wait_synced(zilog
->zl_dmu_pool
, txg
);
1880 ASSERT(error
== ENOENT
|| error
== EEXIST
||
1888 * We're actually making an entry, so update lrc_seq to be the
1889 * log record sequence number. Note that this is generally not
1890 * equal to the itx sequence number because not all transactions
1891 * are synchronous, and sometimes spa_sync() gets there first.
1893 lrcb
->lrc_seq
= ++zilog
->zl_lr_seq
;
1894 lwb
->lwb_nused
+= reclen
+ dnow
;
1896 zil_lwb_add_txg(lwb
, txg
);
1898 ASSERT3U(lwb
->lwb_nused
, <=, lwb
->lwb_sz
);
1899 ASSERT0(P2PHASE(lwb
->lwb_nused
, sizeof (uint64_t)));
1903 zilog
->zl_cur_used
+= reclen
;
1911 zil_itx_create(uint64_t txtype
, size_t olrsize
)
1913 size_t itxsize
, lrsize
;
1916 lrsize
= P2ROUNDUP_TYPED(olrsize
, sizeof (uint64_t), size_t);
1917 itxsize
= offsetof(itx_t
, itx_lr
) + lrsize
;
1919 itx
= zio_data_buf_alloc(itxsize
);
1920 itx
->itx_lr
.lrc_txtype
= txtype
;
1921 itx
->itx_lr
.lrc_reclen
= lrsize
;
1922 itx
->itx_lr
.lrc_seq
= 0; /* defensive */
1923 memset((char *)&itx
->itx_lr
+ olrsize
, 0, lrsize
- olrsize
);
1924 itx
->itx_sync
= B_TRUE
; /* default is synchronous */
1925 itx
->itx_callback
= NULL
;
1926 itx
->itx_callback_data
= NULL
;
1927 itx
->itx_size
= itxsize
;
1933 zil_itx_destroy(itx_t
*itx
)
1935 IMPLY(itx
->itx_lr
.lrc_txtype
== TX_COMMIT
, itx
->itx_callback
== NULL
);
1936 IMPLY(itx
->itx_callback
!= NULL
, itx
->itx_lr
.lrc_txtype
!= TX_COMMIT
);
1938 if (itx
->itx_callback
!= NULL
)
1939 itx
->itx_callback(itx
->itx_callback_data
);
1941 zio_data_buf_free(itx
, itx
->itx_size
);
1945 * Free up the sync and async itxs. The itxs_t has already been detached
1946 * so no locks are needed.
1949 zil_itxg_clean(void *arg
)
1956 itx_async_node_t
*ian
;
1958 list
= &itxs
->i_sync_list
;
1959 while ((itx
= list_head(list
)) != NULL
) {
1961 * In the general case, commit itxs will not be found
1962 * here, as they'll be committed to an lwb via
1963 * zil_lwb_commit(), and free'd in that function. Having
1964 * said that, it is still possible for commit itxs to be
1965 * found here, due to the following race:
1967 * - a thread calls zil_commit() which assigns the
1968 * commit itx to a per-txg i_sync_list
1969 * - zil_itxg_clean() is called (e.g. via spa_sync())
1970 * while the waiter is still on the i_sync_list
1972 * There's nothing to prevent syncing the txg while the
1973 * waiter is on the i_sync_list. This normally doesn't
1974 * happen because spa_sync() is slower than zil_commit(),
1975 * but if zil_commit() calls txg_wait_synced() (e.g.
1976 * because zil_create() or zil_commit_writer_stall() is
1977 * called) we will hit this case.
1979 if (itx
->itx_lr
.lrc_txtype
== TX_COMMIT
)
1980 zil_commit_waiter_skip(itx
->itx_private
);
1982 list_remove(list
, itx
);
1983 zil_itx_destroy(itx
);
1987 t
= &itxs
->i_async_tree
;
1988 while ((ian
= avl_destroy_nodes(t
, &cookie
)) != NULL
) {
1989 list
= &ian
->ia_list
;
1990 while ((itx
= list_head(list
)) != NULL
) {
1991 list_remove(list
, itx
);
1992 /* commit itxs should never be on the async lists. */
1993 ASSERT3U(itx
->itx_lr
.lrc_txtype
, !=, TX_COMMIT
);
1994 zil_itx_destroy(itx
);
1997 kmem_free(ian
, sizeof (itx_async_node_t
));
2001 kmem_free(itxs
, sizeof (itxs_t
));
2005 zil_aitx_compare(const void *x1
, const void *x2
)
2007 const uint64_t o1
= ((itx_async_node_t
*)x1
)->ia_foid
;
2008 const uint64_t o2
= ((itx_async_node_t
*)x2
)->ia_foid
;
2010 return (TREE_CMP(o1
, o2
));
2014 * Remove all async itx with the given oid.
2017 zil_remove_async(zilog_t
*zilog
, uint64_t oid
)
2020 itx_async_node_t
*ian
;
2027 list_create(&clean_list
, sizeof (itx_t
), offsetof(itx_t
, itx_node
));
2029 if (spa_freeze_txg(zilog
->zl_spa
) != UINT64_MAX
) /* ziltest support */
2032 otxg
= spa_last_synced_txg(zilog
->zl_spa
) + 1;
2034 for (txg
= otxg
; txg
< (otxg
+ TXG_CONCURRENT_STATES
); txg
++) {
2035 itxg_t
*itxg
= &zilog
->zl_itxg
[txg
& TXG_MASK
];
2037 mutex_enter(&itxg
->itxg_lock
);
2038 if (itxg
->itxg_txg
!= txg
) {
2039 mutex_exit(&itxg
->itxg_lock
);
2044 * Locate the object node and append its list.
2046 t
= &itxg
->itxg_itxs
->i_async_tree
;
2047 ian
= avl_find(t
, &oid
, &where
);
2049 list_move_tail(&clean_list
, &ian
->ia_list
);
2050 mutex_exit(&itxg
->itxg_lock
);
2052 while ((itx
= list_head(&clean_list
)) != NULL
) {
2053 list_remove(&clean_list
, itx
);
2054 /* commit itxs should never be on the async lists. */
2055 ASSERT3U(itx
->itx_lr
.lrc_txtype
, !=, TX_COMMIT
);
2056 zil_itx_destroy(itx
);
2058 list_destroy(&clean_list
);
2062 zil_itx_assign(zilog_t
*zilog
, itx_t
*itx
, dmu_tx_t
*tx
)
2066 itxs_t
*itxs
, *clean
= NULL
;
2069 * Ensure the data of a renamed file is committed before the rename.
2071 if ((itx
->itx_lr
.lrc_txtype
& ~TX_CI
) == TX_RENAME
)
2072 zil_async_to_sync(zilog
, itx
->itx_oid
);
2074 if (spa_freeze_txg(zilog
->zl_spa
) != UINT64_MAX
)
2077 txg
= dmu_tx_get_txg(tx
);
2079 itxg
= &zilog
->zl_itxg
[txg
& TXG_MASK
];
2080 mutex_enter(&itxg
->itxg_lock
);
2081 itxs
= itxg
->itxg_itxs
;
2082 if (itxg
->itxg_txg
!= txg
) {
2085 * The zil_clean callback hasn't got around to cleaning
2086 * this itxg. Save the itxs for release below.
2087 * This should be rare.
2089 zfs_dbgmsg("zil_itx_assign: missed itx cleanup for "
2090 "txg %llu", (u_longlong_t
)itxg
->itxg_txg
);
2091 clean
= itxg
->itxg_itxs
;
2093 itxg
->itxg_txg
= txg
;
2094 itxs
= itxg
->itxg_itxs
= kmem_zalloc(sizeof (itxs_t
),
2097 list_create(&itxs
->i_sync_list
, sizeof (itx_t
),
2098 offsetof(itx_t
, itx_node
));
2099 avl_create(&itxs
->i_async_tree
, zil_aitx_compare
,
2100 sizeof (itx_async_node_t
),
2101 offsetof(itx_async_node_t
, ia_node
));
2103 if (itx
->itx_sync
) {
2104 list_insert_tail(&itxs
->i_sync_list
, itx
);
2106 avl_tree_t
*t
= &itxs
->i_async_tree
;
2108 LR_FOID_GET_OBJ(((lr_ooo_t
*)&itx
->itx_lr
)->lr_foid
);
2109 itx_async_node_t
*ian
;
2112 ian
= avl_find(t
, &foid
, &where
);
2114 ian
= kmem_alloc(sizeof (itx_async_node_t
),
2116 list_create(&ian
->ia_list
, sizeof (itx_t
),
2117 offsetof(itx_t
, itx_node
));
2118 ian
->ia_foid
= foid
;
2119 avl_insert(t
, ian
, where
);
2121 list_insert_tail(&ian
->ia_list
, itx
);
2124 itx
->itx_lr
.lrc_txg
= dmu_tx_get_txg(tx
);
2127 * We don't want to dirty the ZIL using ZILTEST_TXG, because
2128 * zil_clean() will never be called using ZILTEST_TXG. Thus, we
2129 * need to be careful to always dirty the ZIL using the "real"
2130 * TXG (not itxg_txg) even when the SPA is frozen.
2132 zilog_dirty(zilog
, dmu_tx_get_txg(tx
));
2133 mutex_exit(&itxg
->itxg_lock
);
2135 /* Release the old itxs now we've dropped the lock */
2137 zil_itxg_clean(clean
);
2141 * If there are any in-memory intent log transactions which have now been
2142 * synced then start up a taskq to free them. We should only do this after we
2143 * have written out the uberblocks (i.e. txg has been committed) so that
2144 * don't inadvertently clean out in-memory log records that would be required
2148 zil_clean(zilog_t
*zilog
, uint64_t synced_txg
)
2150 itxg_t
*itxg
= &zilog
->zl_itxg
[synced_txg
& TXG_MASK
];
2153 ASSERT3U(synced_txg
, <, ZILTEST_TXG
);
2155 mutex_enter(&itxg
->itxg_lock
);
2156 if (itxg
->itxg_itxs
== NULL
|| itxg
->itxg_txg
== ZILTEST_TXG
) {
2157 mutex_exit(&itxg
->itxg_lock
);
2160 ASSERT3U(itxg
->itxg_txg
, <=, synced_txg
);
2161 ASSERT3U(itxg
->itxg_txg
, !=, 0);
2162 clean_me
= itxg
->itxg_itxs
;
2163 itxg
->itxg_itxs
= NULL
;
2165 mutex_exit(&itxg
->itxg_lock
);
2167 * Preferably start a task queue to free up the old itxs but
2168 * if taskq_dispatch can't allocate resources to do that then
2169 * free it in-line. This should be rare. Note, using TQ_SLEEP
2170 * created a bad performance problem.
2172 ASSERT3P(zilog
->zl_dmu_pool
, !=, NULL
);
2173 ASSERT3P(zilog
->zl_dmu_pool
->dp_zil_clean_taskq
, !=, NULL
);
2174 taskqid_t id
= taskq_dispatch(zilog
->zl_dmu_pool
->dp_zil_clean_taskq
,
2175 zil_itxg_clean
, clean_me
, TQ_NOSLEEP
);
2176 if (id
== TASKQID_INVALID
)
2177 zil_itxg_clean(clean_me
);
2181 * This function will traverse the queue of itxs that need to be
2182 * committed, and move them onto the ZIL's zl_itx_commit_list.
2185 zil_get_commit_list(zilog_t
*zilog
)
2188 list_t
*commit_list
= &zilog
->zl_itx_commit_list
;
2190 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
2192 if (spa_freeze_txg(zilog
->zl_spa
) != UINT64_MAX
) /* ziltest support */
2195 otxg
= spa_last_synced_txg(zilog
->zl_spa
) + 1;
2198 * This is inherently racy, since there is nothing to prevent
2199 * the last synced txg from changing. That's okay since we'll
2200 * only commit things in the future.
2202 for (txg
= otxg
; txg
< (otxg
+ TXG_CONCURRENT_STATES
); txg
++) {
2203 itxg_t
*itxg
= &zilog
->zl_itxg
[txg
& TXG_MASK
];
2205 mutex_enter(&itxg
->itxg_lock
);
2206 if (itxg
->itxg_txg
!= txg
) {
2207 mutex_exit(&itxg
->itxg_lock
);
2212 * If we're adding itx records to the zl_itx_commit_list,
2213 * then the zil better be dirty in this "txg". We can assert
2214 * that here since we're holding the itxg_lock which will
2215 * prevent spa_sync from cleaning it. Once we add the itxs
2216 * to the zl_itx_commit_list we must commit it to disk even
2217 * if it's unnecessary (i.e. the txg was synced).
2219 ASSERT(zilog_is_dirty_in_txg(zilog
, txg
) ||
2220 spa_freeze_txg(zilog
->zl_spa
) != UINT64_MAX
);
2221 list_move_tail(commit_list
, &itxg
->itxg_itxs
->i_sync_list
);
2223 mutex_exit(&itxg
->itxg_lock
);
2228 * Move the async itxs for a specified object to commit into sync lists.
2231 zil_async_to_sync(zilog_t
*zilog
, uint64_t foid
)
2234 itx_async_node_t
*ian
;
2238 if (spa_freeze_txg(zilog
->zl_spa
) != UINT64_MAX
) /* ziltest support */
2241 otxg
= spa_last_synced_txg(zilog
->zl_spa
) + 1;
2244 * This is inherently racy, since there is nothing to prevent
2245 * the last synced txg from changing.
2247 for (txg
= otxg
; txg
< (otxg
+ TXG_CONCURRENT_STATES
); txg
++) {
2248 itxg_t
*itxg
= &zilog
->zl_itxg
[txg
& TXG_MASK
];
2250 mutex_enter(&itxg
->itxg_lock
);
2251 if (itxg
->itxg_txg
!= txg
) {
2252 mutex_exit(&itxg
->itxg_lock
);
2257 * If a foid is specified then find that node and append its
2258 * list. Otherwise walk the tree appending all the lists
2259 * to the sync list. We add to the end rather than the
2260 * beginning to ensure the create has happened.
2262 t
= &itxg
->itxg_itxs
->i_async_tree
;
2264 ian
= avl_find(t
, &foid
, &where
);
2266 list_move_tail(&itxg
->itxg_itxs
->i_sync_list
,
2270 void *cookie
= NULL
;
2272 while ((ian
= avl_destroy_nodes(t
, &cookie
)) != NULL
) {
2273 list_move_tail(&itxg
->itxg_itxs
->i_sync_list
,
2275 list_destroy(&ian
->ia_list
);
2276 kmem_free(ian
, sizeof (itx_async_node_t
));
2279 mutex_exit(&itxg
->itxg_lock
);
2284 * This function will prune commit itxs that are at the head of the
2285 * commit list (it won't prune past the first non-commit itx), and
2286 * either: a) attach them to the last lwb that's still pending
2287 * completion, or b) skip them altogether.
2289 * This is used as a performance optimization to prevent commit itxs
2290 * from generating new lwbs when it's unnecessary to do so.
2293 zil_prune_commit_list(zilog_t
*zilog
)
2297 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
2299 while ((itx
= list_head(&zilog
->zl_itx_commit_list
)) != NULL
) {
2300 lr_t
*lrc
= &itx
->itx_lr
;
2301 if (lrc
->lrc_txtype
!= TX_COMMIT
)
2304 mutex_enter(&zilog
->zl_lock
);
2306 lwb_t
*last_lwb
= zilog
->zl_last_lwb_opened
;
2307 if (last_lwb
== NULL
||
2308 last_lwb
->lwb_state
== LWB_STATE_FLUSH_DONE
) {
2310 * All of the itxs this waiter was waiting on
2311 * must have already completed (or there were
2312 * never any itx's for it to wait on), so it's
2313 * safe to skip this waiter and mark it done.
2315 zil_commit_waiter_skip(itx
->itx_private
);
2317 zil_commit_waiter_link_lwb(itx
->itx_private
, last_lwb
);
2318 itx
->itx_private
= NULL
;
2321 mutex_exit(&zilog
->zl_lock
);
2323 list_remove(&zilog
->zl_itx_commit_list
, itx
);
2324 zil_itx_destroy(itx
);
2327 IMPLY(itx
!= NULL
, itx
->itx_lr
.lrc_txtype
!= TX_COMMIT
);
2331 zil_commit_writer_stall(zilog_t
*zilog
)
2334 * When zio_alloc_zil() fails to allocate the next lwb block on
2335 * disk, we must call txg_wait_synced() to ensure all of the
2336 * lwbs in the zilog's zl_lwb_list are synced and then freed (in
2337 * zil_sync()), such that any subsequent ZIL writer (i.e. a call
2338 * to zil_process_commit_list()) will have to call zil_create(),
2339 * and start a new ZIL chain.
2341 * Since zil_alloc_zil() failed, the lwb that was previously
2342 * issued does not have a pointer to the "next" lwb on disk.
2343 * Thus, if another ZIL writer thread was to allocate the "next"
2344 * on-disk lwb, that block could be leaked in the event of a
2345 * crash (because the previous lwb on-disk would not point to
2348 * We must hold the zilog's zl_issuer_lock while we do this, to
2349 * ensure no new threads enter zil_process_commit_list() until
2350 * all lwb's in the zl_lwb_list have been synced and freed
2351 * (which is achieved via the txg_wait_synced() call).
2353 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
2354 txg_wait_synced(zilog
->zl_dmu_pool
, 0);
2355 ASSERT3P(list_tail(&zilog
->zl_lwb_list
), ==, NULL
);
2359 * This function will traverse the commit list, creating new lwbs as
2360 * needed, and committing the itxs from the commit list to these newly
2361 * created lwbs. Additionally, as a new lwb is created, the previous
2362 * lwb will be issued to the zio layer to be written to disk.
2365 zil_process_commit_list(zilog_t
*zilog
)
2367 spa_t
*spa
= zilog
->zl_spa
;
2369 list_t nolwb_waiters
;
2373 ASSERT(MUTEX_HELD(&zilog
->zl_issuer_lock
));
2376 * Return if there's nothing to commit before we dirty the fs by
2377 * calling zil_create().
2379 if (list_head(&zilog
->zl_itx_commit_list
) == NULL
)
2382 list_create(&nolwb_itxs
, sizeof (itx_t
), offsetof(itx_t
, itx_node
));
2383 list_create(&nolwb_waiters
, sizeof (zil_commit_waiter_t
),
2384 offsetof(zil_commit_waiter_t
, zcw_node
));
2386 lwb
= list_tail(&zilog
->zl_lwb_list
);
2388 lwb
= zil_create(zilog
);
2391 * Activate SPA_FEATURE_ZILSAXATTR for the cases where ZIL will
2392 * have already been created (zl_lwb_list not empty).
2394 zil_commit_activate_saxattr_feature(zilog
);
2395 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_ISSUED
);
2396 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_WRITE_DONE
);
2397 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_FLUSH_DONE
);
2400 while ((itx
= list_head(&zilog
->zl_itx_commit_list
)) != NULL
) {
2401 lr_t
*lrc
= &itx
->itx_lr
;
2402 uint64_t txg
= lrc
->lrc_txg
;
2404 ASSERT3U(txg
, !=, 0);
2406 if (lrc
->lrc_txtype
== TX_COMMIT
) {
2407 DTRACE_PROBE2(zil__process__commit__itx
,
2408 zilog_t
*, zilog
, itx_t
*, itx
);
2410 DTRACE_PROBE2(zil__process__normal__itx
,
2411 zilog_t
*, zilog
, itx_t
*, itx
);
2414 list_remove(&zilog
->zl_itx_commit_list
, itx
);
2416 boolean_t synced
= txg
<= spa_last_synced_txg(spa
);
2417 boolean_t frozen
= txg
> spa_freeze_txg(spa
);
2420 * If the txg of this itx has already been synced out, then
2421 * we don't need to commit this itx to an lwb. This is
2422 * because the data of this itx will have already been
2423 * written to the main pool. This is inherently racy, and
2424 * it's still ok to commit an itx whose txg has already
2425 * been synced; this will result in a write that's
2426 * unnecessary, but will do no harm.
2428 * With that said, we always want to commit TX_COMMIT itxs
2429 * to an lwb, regardless of whether or not that itx's txg
2430 * has been synced out. We do this to ensure any OPENED lwb
2431 * will always have at least one zil_commit_waiter_t linked
2434 * As a counter-example, if we skipped TX_COMMIT itx's
2435 * whose txg had already been synced, the following
2436 * situation could occur if we happened to be racing with
2439 * 1. We commit a non-TX_COMMIT itx to an lwb, where the
2440 * itx's txg is 10 and the last synced txg is 9.
2441 * 2. spa_sync finishes syncing out txg 10.
2442 * 3. We move to the next itx in the list, it's a TX_COMMIT
2443 * whose txg is 10, so we skip it rather than committing
2444 * it to the lwb used in (1).
2446 * If the itx that is skipped in (3) is the last TX_COMMIT
2447 * itx in the commit list, than it's possible for the lwb
2448 * used in (1) to remain in the OPENED state indefinitely.
2450 * To prevent the above scenario from occurring, ensuring
2451 * that once an lwb is OPENED it will transition to ISSUED
2452 * and eventually DONE, we always commit TX_COMMIT itx's to
2453 * an lwb here, even if that itx's txg has already been
2456 * Finally, if the pool is frozen, we _always_ commit the
2457 * itx. The point of freezing the pool is to prevent data
2458 * from being written to the main pool via spa_sync, and
2459 * instead rely solely on the ZIL to persistently store the
2460 * data; i.e. when the pool is frozen, the last synced txg
2461 * value can't be trusted.
2463 if (frozen
|| !synced
|| lrc
->lrc_txtype
== TX_COMMIT
) {
2465 lwb
= zil_lwb_commit(zilog
, itx
, lwb
);
2468 list_insert_tail(&nolwb_itxs
, itx
);
2470 list_insert_tail(&lwb
->lwb_itxs
, itx
);
2472 if (lrc
->lrc_txtype
== TX_COMMIT
) {
2473 zil_commit_waiter_link_nolwb(
2474 itx
->itx_private
, &nolwb_waiters
);
2477 list_insert_tail(&nolwb_itxs
, itx
);
2480 ASSERT3S(lrc
->lrc_txtype
, !=, TX_COMMIT
);
2481 zil_itx_destroy(itx
);
2487 * This indicates zio_alloc_zil() failed to allocate the
2488 * "next" lwb on-disk. When this happens, we must stall
2489 * the ZIL write pipeline; see the comment within
2490 * zil_commit_writer_stall() for more details.
2492 zil_commit_writer_stall(zilog
);
2495 * Additionally, we have to signal and mark the "nolwb"
2496 * waiters as "done" here, since without an lwb, we
2497 * can't do this via zil_lwb_flush_vdevs_done() like
2500 zil_commit_waiter_t
*zcw
;
2501 while ((zcw
= list_head(&nolwb_waiters
)) != NULL
) {
2502 zil_commit_waiter_skip(zcw
);
2503 list_remove(&nolwb_waiters
, zcw
);
2507 * And finally, we have to destroy the itx's that
2508 * couldn't be committed to an lwb; this will also call
2509 * the itx's callback if one exists for the itx.
2511 while ((itx
= list_head(&nolwb_itxs
)) != NULL
) {
2512 list_remove(&nolwb_itxs
, itx
);
2513 zil_itx_destroy(itx
);
2516 ASSERT(list_is_empty(&nolwb_waiters
));
2517 ASSERT3P(lwb
, !=, NULL
);
2518 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_ISSUED
);
2519 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_WRITE_DONE
);
2520 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_FLUSH_DONE
);
2523 * At this point, the ZIL block pointed at by the "lwb"
2524 * variable is in one of the following states: "closed"
2527 * If it's "closed", then no itxs have been committed to
2528 * it, so there's no point in issuing its zio (i.e. it's
2531 * If it's "open", then it contains one or more itxs that
2532 * eventually need to be committed to stable storage. In
2533 * this case we intentionally do not issue the lwb's zio
2534 * to disk yet, and instead rely on one of the following
2535 * two mechanisms for issuing the zio:
2537 * 1. Ideally, there will be more ZIL activity occurring
2538 * on the system, such that this function will be
2539 * immediately called again (not necessarily by the same
2540 * thread) and this lwb's zio will be issued via
2541 * zil_lwb_commit(). This way, the lwb is guaranteed to
2542 * be "full" when it is issued to disk, and we'll make
2543 * use of the lwb's size the best we can.
2545 * 2. If there isn't sufficient ZIL activity occurring on
2546 * the system, such that this lwb's zio isn't issued via
2547 * zil_lwb_commit(), zil_commit_waiter() will issue the
2548 * lwb's zio. If this occurs, the lwb is not guaranteed
2549 * to be "full" by the time its zio is issued, and means
2550 * the size of the lwb was "too large" given the amount
2551 * of ZIL activity occurring on the system at that time.
2553 * We do this for a couple of reasons:
2555 * 1. To try and reduce the number of IOPs needed to
2556 * write the same number of itxs. If an lwb has space
2557 * available in its buffer for more itxs, and more itxs
2558 * will be committed relatively soon (relative to the
2559 * latency of performing a write), then it's beneficial
2560 * to wait for these "next" itxs. This way, more itxs
2561 * can be committed to stable storage with fewer writes.
2563 * 2. To try and use the largest lwb block size that the
2564 * incoming rate of itxs can support. Again, this is to
2565 * try and pack as many itxs into as few lwbs as
2566 * possible, without significantly impacting the latency
2567 * of each individual itx.
2573 * This function is responsible for ensuring the passed in commit waiter
2574 * (and associated commit itx) is committed to an lwb. If the waiter is
2575 * not already committed to an lwb, all itxs in the zilog's queue of
2576 * itxs will be processed. The assumption is the passed in waiter's
2577 * commit itx will found in the queue just like the other non-commit
2578 * itxs, such that when the entire queue is processed, the waiter will
2579 * have been committed to an lwb.
2581 * The lwb associated with the passed in waiter is not guaranteed to
2582 * have been issued by the time this function completes. If the lwb is
2583 * not issued, we rely on future calls to zil_commit_writer() to issue
2584 * the lwb, or the timeout mechanism found in zil_commit_waiter().
2587 zil_commit_writer(zilog_t
*zilog
, zil_commit_waiter_t
*zcw
)
2589 ASSERT(!MUTEX_HELD(&zilog
->zl_lock
));
2590 ASSERT(spa_writeable(zilog
->zl_spa
));
2592 mutex_enter(&zilog
->zl_issuer_lock
);
2594 if (zcw
->zcw_lwb
!= NULL
|| zcw
->zcw_done
) {
2596 * It's possible that, while we were waiting to acquire
2597 * the "zl_issuer_lock", another thread committed this
2598 * waiter to an lwb. If that occurs, we bail out early,
2599 * without processing any of the zilog's queue of itxs.
2601 * On certain workloads and system configurations, the
2602 * "zl_issuer_lock" can become highly contended. In an
2603 * attempt to reduce this contention, we immediately drop
2604 * the lock if the waiter has already been processed.
2606 * We've measured this optimization to reduce CPU spent
2607 * contending on this lock by up to 5%, using a system
2608 * with 32 CPUs, low latency storage (~50 usec writes),
2609 * and 1024 threads performing sync writes.
2614 ZIL_STAT_BUMP(zil_commit_writer_count
);
2616 zil_get_commit_list(zilog
);
2617 zil_prune_commit_list(zilog
);
2618 zil_process_commit_list(zilog
);
2621 mutex_exit(&zilog
->zl_issuer_lock
);
2625 zil_commit_waiter_timeout(zilog_t
*zilog
, zil_commit_waiter_t
*zcw
)
2627 ASSERT(!MUTEX_HELD(&zilog
->zl_issuer_lock
));
2628 ASSERT(MUTEX_HELD(&zcw
->zcw_lock
));
2629 ASSERT3B(zcw
->zcw_done
, ==, B_FALSE
);
2631 lwb_t
*lwb
= zcw
->zcw_lwb
;
2632 ASSERT3P(lwb
, !=, NULL
);
2633 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_CLOSED
);
2636 * If the lwb has already been issued by another thread, we can
2637 * immediately return since there's no work to be done (the
2638 * point of this function is to issue the lwb). Additionally, we
2639 * do this prior to acquiring the zl_issuer_lock, to avoid
2640 * acquiring it when it's not necessary to do so.
2642 if (lwb
->lwb_state
== LWB_STATE_ISSUED
||
2643 lwb
->lwb_state
== LWB_STATE_WRITE_DONE
||
2644 lwb
->lwb_state
== LWB_STATE_FLUSH_DONE
)
2648 * In order to call zil_lwb_write_issue() we must hold the
2649 * zilog's "zl_issuer_lock". We can't simply acquire that lock,
2650 * since we're already holding the commit waiter's "zcw_lock",
2651 * and those two locks are acquired in the opposite order
2654 mutex_exit(&zcw
->zcw_lock
);
2655 mutex_enter(&zilog
->zl_issuer_lock
);
2656 mutex_enter(&zcw
->zcw_lock
);
2659 * Since we just dropped and re-acquired the commit waiter's
2660 * lock, we have to re-check to see if the waiter was marked
2661 * "done" during that process. If the waiter was marked "done",
2662 * the "lwb" pointer is no longer valid (it can be free'd after
2663 * the waiter is marked "done"), so without this check we could
2664 * wind up with a use-after-free error below.
2669 ASSERT3P(lwb
, ==, zcw
->zcw_lwb
);
2672 * We've already checked this above, but since we hadn't acquired
2673 * the zilog's zl_issuer_lock, we have to perform this check a
2674 * second time while holding the lock.
2676 * We don't need to hold the zl_lock since the lwb cannot transition
2677 * from OPENED to ISSUED while we hold the zl_issuer_lock. The lwb
2678 * _can_ transition from ISSUED to DONE, but it's OK to race with
2679 * that transition since we treat the lwb the same, whether it's in
2680 * the ISSUED or DONE states.
2682 * The important thing, is we treat the lwb differently depending on
2683 * if it's ISSUED or OPENED, and block any other threads that might
2684 * attempt to issue this lwb. For that reason we hold the
2685 * zl_issuer_lock when checking the lwb_state; we must not call
2686 * zil_lwb_write_issue() if the lwb had already been issued.
2688 * See the comment above the lwb_state_t structure definition for
2689 * more details on the lwb states, and locking requirements.
2691 if (lwb
->lwb_state
== LWB_STATE_ISSUED
||
2692 lwb
->lwb_state
== LWB_STATE_WRITE_DONE
||
2693 lwb
->lwb_state
== LWB_STATE_FLUSH_DONE
)
2696 ASSERT3S(lwb
->lwb_state
, ==, LWB_STATE_OPENED
);
2699 * As described in the comments above zil_commit_waiter() and
2700 * zil_process_commit_list(), we need to issue this lwb's zio
2701 * since we've reached the commit waiter's timeout and it still
2702 * hasn't been issued.
2704 lwb_t
*nlwb
= zil_lwb_write_issue(zilog
, lwb
);
2706 IMPLY(nlwb
!= NULL
, lwb
->lwb_state
!= LWB_STATE_OPENED
);
2709 * Since the lwb's zio hadn't been issued by the time this thread
2710 * reached its timeout, we reset the zilog's "zl_cur_used" field
2711 * to influence the zil block size selection algorithm.
2713 * By having to issue the lwb's zio here, it means the size of the
2714 * lwb was too large, given the incoming throughput of itxs. By
2715 * setting "zl_cur_used" to zero, we communicate this fact to the
2716 * block size selection algorithm, so it can take this information
2717 * into account, and potentially select a smaller size for the
2718 * next lwb block that is allocated.
2720 zilog
->zl_cur_used
= 0;
2724 * When zil_lwb_write_issue() returns NULL, this
2725 * indicates zio_alloc_zil() failed to allocate the
2726 * "next" lwb on-disk. When this occurs, the ZIL write
2727 * pipeline must be stalled; see the comment within the
2728 * zil_commit_writer_stall() function for more details.
2730 * We must drop the commit waiter's lock prior to
2731 * calling zil_commit_writer_stall() or else we can wind
2732 * up with the following deadlock:
2734 * - This thread is waiting for the txg to sync while
2735 * holding the waiter's lock; txg_wait_synced() is
2736 * used within txg_commit_writer_stall().
2738 * - The txg can't sync because it is waiting for this
2739 * lwb's zio callback to call dmu_tx_commit().
2741 * - The lwb's zio callback can't call dmu_tx_commit()
2742 * because it's blocked trying to acquire the waiter's
2743 * lock, which occurs prior to calling dmu_tx_commit()
2745 mutex_exit(&zcw
->zcw_lock
);
2746 zil_commit_writer_stall(zilog
);
2747 mutex_enter(&zcw
->zcw_lock
);
2751 mutex_exit(&zilog
->zl_issuer_lock
);
2752 ASSERT(MUTEX_HELD(&zcw
->zcw_lock
));
2756 * This function is responsible for performing the following two tasks:
2758 * 1. its primary responsibility is to block until the given "commit
2759 * waiter" is considered "done".
2761 * 2. its secondary responsibility is to issue the zio for the lwb that
2762 * the given "commit waiter" is waiting on, if this function has
2763 * waited "long enough" and the lwb is still in the "open" state.
2765 * Given a sufficient amount of itxs being generated and written using
2766 * the ZIL, the lwb's zio will be issued via the zil_lwb_commit()
2767 * function. If this does not occur, this secondary responsibility will
2768 * ensure the lwb is issued even if there is not other synchronous
2769 * activity on the system.
2771 * For more details, see zil_process_commit_list(); more specifically,
2772 * the comment at the bottom of that function.
2775 zil_commit_waiter(zilog_t
*zilog
, zil_commit_waiter_t
*zcw
)
2777 ASSERT(!MUTEX_HELD(&zilog
->zl_lock
));
2778 ASSERT(!MUTEX_HELD(&zilog
->zl_issuer_lock
));
2779 ASSERT(spa_writeable(zilog
->zl_spa
));
2781 mutex_enter(&zcw
->zcw_lock
);
2784 * The timeout is scaled based on the lwb latency to avoid
2785 * significantly impacting the latency of each individual itx.
2786 * For more details, see the comment at the bottom of the
2787 * zil_process_commit_list() function.
2789 int pct
= MAX(zfs_commit_timeout_pct
, 1);
2790 hrtime_t sleep
= (zilog
->zl_last_lwb_latency
* pct
) / 100;
2791 hrtime_t wakeup
= gethrtime() + sleep
;
2792 boolean_t timedout
= B_FALSE
;
2794 while (!zcw
->zcw_done
) {
2795 ASSERT(MUTEX_HELD(&zcw
->zcw_lock
));
2797 lwb_t
*lwb
= zcw
->zcw_lwb
;
2800 * Usually, the waiter will have a non-NULL lwb field here,
2801 * but it's possible for it to be NULL as a result of
2802 * zil_commit() racing with spa_sync().
2804 * When zil_clean() is called, it's possible for the itxg
2805 * list (which may be cleaned via a taskq) to contain
2806 * commit itxs. When this occurs, the commit waiters linked
2807 * off of these commit itxs will not be committed to an
2808 * lwb. Additionally, these commit waiters will not be
2809 * marked done until zil_commit_waiter_skip() is called via
2812 * Thus, it's possible for this commit waiter (i.e. the
2813 * "zcw" variable) to be found in this "in between" state;
2814 * where it's "zcw_lwb" field is NULL, and it hasn't yet
2815 * been skipped, so it's "zcw_done" field is still B_FALSE.
2817 IMPLY(lwb
!= NULL
, lwb
->lwb_state
!= LWB_STATE_CLOSED
);
2819 if (lwb
!= NULL
&& lwb
->lwb_state
== LWB_STATE_OPENED
) {
2820 ASSERT3B(timedout
, ==, B_FALSE
);
2823 * If the lwb hasn't been issued yet, then we
2824 * need to wait with a timeout, in case this
2825 * function needs to issue the lwb after the
2826 * timeout is reached; responsibility (2) from
2827 * the comment above this function.
2829 int rc
= cv_timedwait_hires(&zcw
->zcw_cv
,
2830 &zcw
->zcw_lock
, wakeup
, USEC2NSEC(1),
2831 CALLOUT_FLAG_ABSOLUTE
);
2833 if (rc
!= -1 || zcw
->zcw_done
)
2837 zil_commit_waiter_timeout(zilog
, zcw
);
2839 if (!zcw
->zcw_done
) {
2841 * If the commit waiter has already been
2842 * marked "done", it's possible for the
2843 * waiter's lwb structure to have already
2844 * been freed. Thus, we can only reliably
2845 * make these assertions if the waiter
2848 ASSERT3P(lwb
, ==, zcw
->zcw_lwb
);
2849 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_OPENED
);
2853 * If the lwb isn't open, then it must have already
2854 * been issued. In that case, there's no need to
2855 * use a timeout when waiting for the lwb to
2858 * Additionally, if the lwb is NULL, the waiter
2859 * will soon be signaled and marked done via
2860 * zil_clean() and zil_itxg_clean(), so no timeout
2865 lwb
->lwb_state
== LWB_STATE_ISSUED
||
2866 lwb
->lwb_state
== LWB_STATE_WRITE_DONE
||
2867 lwb
->lwb_state
== LWB_STATE_FLUSH_DONE
);
2868 cv_wait(&zcw
->zcw_cv
, &zcw
->zcw_lock
);
2872 mutex_exit(&zcw
->zcw_lock
);
2875 static zil_commit_waiter_t
*
2876 zil_alloc_commit_waiter(void)
2878 zil_commit_waiter_t
*zcw
= kmem_cache_alloc(zil_zcw_cache
, KM_SLEEP
);
2880 cv_init(&zcw
->zcw_cv
, NULL
, CV_DEFAULT
, NULL
);
2881 mutex_init(&zcw
->zcw_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
2882 list_link_init(&zcw
->zcw_node
);
2883 zcw
->zcw_lwb
= NULL
;
2884 zcw
->zcw_done
= B_FALSE
;
2885 zcw
->zcw_zio_error
= 0;
2891 zil_free_commit_waiter(zil_commit_waiter_t
*zcw
)
2893 ASSERT(!list_link_active(&zcw
->zcw_node
));
2894 ASSERT3P(zcw
->zcw_lwb
, ==, NULL
);
2895 ASSERT3B(zcw
->zcw_done
, ==, B_TRUE
);
2896 mutex_destroy(&zcw
->zcw_lock
);
2897 cv_destroy(&zcw
->zcw_cv
);
2898 kmem_cache_free(zil_zcw_cache
, zcw
);
2902 * This function is used to create a TX_COMMIT itx and assign it. This
2903 * way, it will be linked into the ZIL's list of synchronous itxs, and
2904 * then later committed to an lwb (or skipped) when
2905 * zil_process_commit_list() is called.
2908 zil_commit_itx_assign(zilog_t
*zilog
, zil_commit_waiter_t
*zcw
)
2910 dmu_tx_t
*tx
= dmu_tx_create(zilog
->zl_os
);
2911 VERIFY0(dmu_tx_assign(tx
, TXG_WAIT
));
2913 itx_t
*itx
= zil_itx_create(TX_COMMIT
, sizeof (lr_t
));
2914 itx
->itx_sync
= B_TRUE
;
2915 itx
->itx_private
= zcw
;
2917 zil_itx_assign(zilog
, itx
, tx
);
2923 * Commit ZFS Intent Log transactions (itxs) to stable storage.
2925 * When writing ZIL transactions to the on-disk representation of the
2926 * ZIL, the itxs are committed to a Log Write Block (lwb). Multiple
2927 * itxs can be committed to a single lwb. Once a lwb is written and
2928 * committed to stable storage (i.e. the lwb is written, and vdevs have
2929 * been flushed), each itx that was committed to that lwb is also
2930 * considered to be committed to stable storage.
2932 * When an itx is committed to an lwb, the log record (lr_t) contained
2933 * by the itx is copied into the lwb's zio buffer, and once this buffer
2934 * is written to disk, it becomes an on-disk ZIL block.
2936 * As itxs are generated, they're inserted into the ZIL's queue of
2937 * uncommitted itxs. The semantics of zil_commit() are such that it will
2938 * block until all itxs that were in the queue when it was called, are
2939 * committed to stable storage.
2941 * If "foid" is zero, this means all "synchronous" and "asynchronous"
2942 * itxs, for all objects in the dataset, will be committed to stable
2943 * storage prior to zil_commit() returning. If "foid" is non-zero, all
2944 * "synchronous" itxs for all objects, but only "asynchronous" itxs
2945 * that correspond to the foid passed in, will be committed to stable
2946 * storage prior to zil_commit() returning.
2948 * Generally speaking, when zil_commit() is called, the consumer doesn't
2949 * actually care about _all_ of the uncommitted itxs. Instead, they're
2950 * simply trying to waiting for a specific itx to be committed to disk,
2951 * but the interface(s) for interacting with the ZIL don't allow such
2952 * fine-grained communication. A better interface would allow a consumer
2953 * to create and assign an itx, and then pass a reference to this itx to
2954 * zil_commit(); such that zil_commit() would return as soon as that
2955 * specific itx was committed to disk (instead of waiting for _all_
2956 * itxs to be committed).
2958 * When a thread calls zil_commit() a special "commit itx" will be
2959 * generated, along with a corresponding "waiter" for this commit itx.
2960 * zil_commit() will wait on this waiter's CV, such that when the waiter
2961 * is marked done, and signaled, zil_commit() will return.
2963 * This commit itx is inserted into the queue of uncommitted itxs. This
2964 * provides an easy mechanism for determining which itxs were in the
2965 * queue prior to zil_commit() having been called, and which itxs were
2966 * added after zil_commit() was called.
2968 * The commit it is special; it doesn't have any on-disk representation.
2969 * When a commit itx is "committed" to an lwb, the waiter associated
2970 * with it is linked onto the lwb's list of waiters. Then, when that lwb
2971 * completes, each waiter on the lwb's list is marked done and signaled
2972 * -- allowing the thread waiting on the waiter to return from zil_commit().
2974 * It's important to point out a few critical factors that allow us
2975 * to make use of the commit itxs, commit waiters, per-lwb lists of
2976 * commit waiters, and zio completion callbacks like we're doing:
2978 * 1. The list of waiters for each lwb is traversed, and each commit
2979 * waiter is marked "done" and signaled, in the zio completion
2980 * callback of the lwb's zio[*].
2982 * * Actually, the waiters are signaled in the zio completion
2983 * callback of the root zio for the DKIOCFLUSHWRITECACHE commands
2984 * that are sent to the vdevs upon completion of the lwb zio.
2986 * 2. When the itxs are inserted into the ZIL's queue of uncommitted
2987 * itxs, the order in which they are inserted is preserved[*]; as
2988 * itxs are added to the queue, they are added to the tail of
2989 * in-memory linked lists.
2991 * When committing the itxs to lwbs (to be written to disk), they
2992 * are committed in the same order in which the itxs were added to
2993 * the uncommitted queue's linked list(s); i.e. the linked list of
2994 * itxs to commit is traversed from head to tail, and each itx is
2995 * committed to an lwb in that order.
2999 * - the order of "sync" itxs is preserved w.r.t. other
3000 * "sync" itxs, regardless of the corresponding objects.
3001 * - the order of "async" itxs is preserved w.r.t. other
3002 * "async" itxs corresponding to the same object.
3003 * - the order of "async" itxs is *not* preserved w.r.t. other
3004 * "async" itxs corresponding to different objects.
3005 * - the order of "sync" itxs w.r.t. "async" itxs (or vice
3006 * versa) is *not* preserved, even for itxs that correspond
3007 * to the same object.
3009 * For more details, see: zil_itx_assign(), zil_async_to_sync(),
3010 * zil_get_commit_list(), and zil_process_commit_list().
3012 * 3. The lwbs represent a linked list of blocks on disk. Thus, any
3013 * lwb cannot be considered committed to stable storage, until its
3014 * "previous" lwb is also committed to stable storage. This fact,
3015 * coupled with the fact described above, means that itxs are
3016 * committed in (roughly) the order in which they were generated.
3017 * This is essential because itxs are dependent on prior itxs.
3018 * Thus, we *must not* deem an itx as being committed to stable
3019 * storage, until *all* prior itxs have also been committed to
3022 * To enforce this ordering of lwb zio's, while still leveraging as
3023 * much of the underlying storage performance as possible, we rely
3024 * on two fundamental concepts:
3026 * 1. The creation and issuance of lwb zio's is protected by
3027 * the zilog's "zl_issuer_lock", which ensures only a single
3028 * thread is creating and/or issuing lwb's at a time
3029 * 2. The "previous" lwb is a child of the "current" lwb
3030 * (leveraging the zio parent-child dependency graph)
3032 * By relying on this parent-child zio relationship, we can have
3033 * many lwb zio's concurrently issued to the underlying storage,
3034 * but the order in which they complete will be the same order in
3035 * which they were created.
3038 zil_commit(zilog_t
*zilog
, uint64_t foid
)
3041 * We should never attempt to call zil_commit on a snapshot for
3042 * a couple of reasons:
3044 * 1. A snapshot may never be modified, thus it cannot have any
3045 * in-flight itxs that would have modified the dataset.
3047 * 2. By design, when zil_commit() is called, a commit itx will
3048 * be assigned to this zilog; as a result, the zilog will be
3049 * dirtied. We must not dirty the zilog of a snapshot; there's
3050 * checks in the code that enforce this invariant, and will
3051 * cause a panic if it's not upheld.
3053 ASSERT3B(dmu_objset_is_snapshot(zilog
->zl_os
), ==, B_FALSE
);
3055 if (zilog
->zl_sync
== ZFS_SYNC_DISABLED
)
3058 if (!spa_writeable(zilog
->zl_spa
)) {
3060 * If the SPA is not writable, there should never be any
3061 * pending itxs waiting to be committed to disk. If that
3062 * weren't true, we'd skip writing those itxs out, and
3063 * would break the semantics of zil_commit(); thus, we're
3064 * verifying that truth before we return to the caller.
3066 ASSERT(list_is_empty(&zilog
->zl_lwb_list
));
3067 ASSERT3P(zilog
->zl_last_lwb_opened
, ==, NULL
);
3068 for (int i
= 0; i
< TXG_SIZE
; i
++)
3069 ASSERT3P(zilog
->zl_itxg
[i
].itxg_itxs
, ==, NULL
);
3074 * If the ZIL is suspended, we don't want to dirty it by calling
3075 * zil_commit_itx_assign() below, nor can we write out
3076 * lwbs like would be done in zil_commit_write(). Thus, we
3077 * simply rely on txg_wait_synced() to maintain the necessary
3078 * semantics, and avoid calling those functions altogether.
3080 if (zilog
->zl_suspend
> 0) {
3081 txg_wait_synced(zilog
->zl_dmu_pool
, 0);
3085 zil_commit_impl(zilog
, foid
);
3089 zil_commit_impl(zilog_t
*zilog
, uint64_t foid
)
3091 ZIL_STAT_BUMP(zil_commit_count
);
3094 * Move the "async" itxs for the specified foid to the "sync"
3095 * queues, such that they will be later committed (or skipped)
3096 * to an lwb when zil_process_commit_list() is called.
3098 * Since these "async" itxs must be committed prior to this
3099 * call to zil_commit returning, we must perform this operation
3100 * before we call zil_commit_itx_assign().
3102 zil_async_to_sync(zilog
, foid
);
3105 * We allocate a new "waiter" structure which will initially be
3106 * linked to the commit itx using the itx's "itx_private" field.
3107 * Since the commit itx doesn't represent any on-disk state,
3108 * when it's committed to an lwb, rather than copying the its
3109 * lr_t into the lwb's buffer, the commit itx's "waiter" will be
3110 * added to the lwb's list of waiters. Then, when the lwb is
3111 * committed to stable storage, each waiter in the lwb's list of
3112 * waiters will be marked "done", and signalled.
3114 * We must create the waiter and assign the commit itx prior to
3115 * calling zil_commit_writer(), or else our specific commit itx
3116 * is not guaranteed to be committed to an lwb prior to calling
3117 * zil_commit_waiter().
3119 zil_commit_waiter_t
*zcw
= zil_alloc_commit_waiter();
3120 zil_commit_itx_assign(zilog
, zcw
);
3122 zil_commit_writer(zilog
, zcw
);
3123 zil_commit_waiter(zilog
, zcw
);
3125 if (zcw
->zcw_zio_error
!= 0) {
3127 * If there was an error writing out the ZIL blocks that
3128 * this thread is waiting on, then we fallback to
3129 * relying on spa_sync() to write out the data this
3130 * thread is waiting on. Obviously this has performance
3131 * implications, but the expectation is for this to be
3132 * an exceptional case, and shouldn't occur often.
3134 DTRACE_PROBE2(zil__commit__io__error
,
3135 zilog_t
*, zilog
, zil_commit_waiter_t
*, zcw
);
3136 txg_wait_synced(zilog
->zl_dmu_pool
, 0);
3139 zil_free_commit_waiter(zcw
);
3143 * Called in syncing context to free committed log blocks and update log header.
3146 zil_sync(zilog_t
*zilog
, dmu_tx_t
*tx
)
3148 zil_header_t
*zh
= zil_header_in_syncing_context(zilog
);
3149 uint64_t txg
= dmu_tx_get_txg(tx
);
3150 spa_t
*spa
= zilog
->zl_spa
;
3151 uint64_t *replayed_seq
= &zilog
->zl_replayed_seq
[txg
& TXG_MASK
];
3155 * We don't zero out zl_destroy_txg, so make sure we don't try
3156 * to destroy it twice.
3158 if (spa_sync_pass(spa
) != 1)
3161 zil_lwb_flush_wait_all(zilog
, txg
);
3163 mutex_enter(&zilog
->zl_lock
);
3165 ASSERT(zilog
->zl_stop_sync
== 0);
3167 if (*replayed_seq
!= 0) {
3168 ASSERT(zh
->zh_replay_seq
< *replayed_seq
);
3169 zh
->zh_replay_seq
= *replayed_seq
;
3173 if (zilog
->zl_destroy_txg
== txg
) {
3174 blkptr_t blk
= zh
->zh_log
;
3175 dsl_dataset_t
*ds
= dmu_objset_ds(zilog
->zl_os
);
3177 ASSERT(list_head(&zilog
->zl_lwb_list
) == NULL
);
3179 memset(zh
, 0, sizeof (zil_header_t
));
3180 memset(zilog
->zl_replayed_seq
, 0,
3181 sizeof (zilog
->zl_replayed_seq
));
3183 if (zilog
->zl_keep_first
) {
3185 * If this block was part of log chain that couldn't
3186 * be claimed because a device was missing during
3187 * zil_claim(), but that device later returns,
3188 * then this block could erroneously appear valid.
3189 * To guard against this, assign a new GUID to the new
3190 * log chain so it doesn't matter what blk points to.
3192 zil_init_log_chain(zilog
, &blk
);
3196 * A destroyed ZIL chain can't contain any TX_SETSAXATTR
3197 * records. So, deactivate the feature for this dataset.
3198 * We activate it again when we start a new ZIL chain.
3200 if (dsl_dataset_feature_is_active(ds
,
3201 SPA_FEATURE_ZILSAXATTR
))
3202 dsl_dataset_deactivate_feature(ds
,
3203 SPA_FEATURE_ZILSAXATTR
, tx
);
3207 while ((lwb
= list_head(&zilog
->zl_lwb_list
)) != NULL
) {
3208 zh
->zh_log
= lwb
->lwb_blk
;
3209 if (lwb
->lwb_buf
!= NULL
|| lwb
->lwb_max_txg
> txg
)
3211 list_remove(&zilog
->zl_lwb_list
, lwb
);
3212 zio_free(spa
, txg
, &lwb
->lwb_blk
);
3213 zil_free_lwb(zilog
, lwb
);
3216 * If we don't have anything left in the lwb list then
3217 * we've had an allocation failure and we need to zero
3218 * out the zil_header blkptr so that we don't end
3219 * up freeing the same block twice.
3221 if (list_head(&zilog
->zl_lwb_list
) == NULL
)
3222 BP_ZERO(&zh
->zh_log
);
3226 * Remove fastwrite on any blocks that have been pre-allocated for
3227 * the next commit. This prevents fastwrite counter pollution by
3228 * unused, long-lived LWBs.
3230 for (; lwb
!= NULL
; lwb
= list_next(&zilog
->zl_lwb_list
, lwb
)) {
3231 if (lwb
->lwb_fastwrite
&& !lwb
->lwb_write_zio
) {
3232 metaslab_fastwrite_unmark(zilog
->zl_spa
, &lwb
->lwb_blk
);
3233 lwb
->lwb_fastwrite
= 0;
3237 mutex_exit(&zilog
->zl_lock
);
3241 zil_lwb_cons(void *vbuf
, void *unused
, int kmflag
)
3243 (void) unused
, (void) kmflag
;
3245 list_create(&lwb
->lwb_itxs
, sizeof (itx_t
), offsetof(itx_t
, itx_node
));
3246 list_create(&lwb
->lwb_waiters
, sizeof (zil_commit_waiter_t
),
3247 offsetof(zil_commit_waiter_t
, zcw_node
));
3248 avl_create(&lwb
->lwb_vdev_tree
, zil_lwb_vdev_compare
,
3249 sizeof (zil_vdev_node_t
), offsetof(zil_vdev_node_t
, zv_node
));
3250 mutex_init(&lwb
->lwb_vdev_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
3255 zil_lwb_dest(void *vbuf
, void *unused
)
3259 mutex_destroy(&lwb
->lwb_vdev_lock
);
3260 avl_destroy(&lwb
->lwb_vdev_tree
);
3261 list_destroy(&lwb
->lwb_waiters
);
3262 list_destroy(&lwb
->lwb_itxs
);
3268 zil_lwb_cache
= kmem_cache_create("zil_lwb_cache",
3269 sizeof (lwb_t
), 0, zil_lwb_cons
, zil_lwb_dest
, NULL
, NULL
, NULL
, 0);
3271 zil_zcw_cache
= kmem_cache_create("zil_zcw_cache",
3272 sizeof (zil_commit_waiter_t
), 0, NULL
, NULL
, NULL
, NULL
, NULL
, 0);
3274 zil_ksp
= kstat_create("zfs", 0, "zil", "misc",
3275 KSTAT_TYPE_NAMED
, sizeof (zil_stats
) / sizeof (kstat_named_t
),
3276 KSTAT_FLAG_VIRTUAL
);
3278 if (zil_ksp
!= NULL
) {
3279 zil_ksp
->ks_data
= &zil_stats
;
3280 kstat_install(zil_ksp
);
3287 kmem_cache_destroy(zil_zcw_cache
);
3288 kmem_cache_destroy(zil_lwb_cache
);
3290 if (zil_ksp
!= NULL
) {
3291 kstat_delete(zil_ksp
);
3297 zil_set_sync(zilog_t
*zilog
, uint64_t sync
)
3299 zilog
->zl_sync
= sync
;
3303 zil_set_logbias(zilog_t
*zilog
, uint64_t logbias
)
3305 zilog
->zl_logbias
= logbias
;
3309 zil_alloc(objset_t
*os
, zil_header_t
*zh_phys
)
3313 zilog
= kmem_zalloc(sizeof (zilog_t
), KM_SLEEP
);
3315 zilog
->zl_header
= zh_phys
;
3317 zilog
->zl_spa
= dmu_objset_spa(os
);
3318 zilog
->zl_dmu_pool
= dmu_objset_pool(os
);
3319 zilog
->zl_destroy_txg
= TXG_INITIAL
- 1;
3320 zilog
->zl_logbias
= dmu_objset_logbias(os
);
3321 zilog
->zl_sync
= dmu_objset_syncprop(os
);
3322 zilog
->zl_dirty_max_txg
= 0;
3323 zilog
->zl_last_lwb_opened
= NULL
;
3324 zilog
->zl_last_lwb_latency
= 0;
3325 zilog
->zl_max_block_size
= zil_maxblocksize
;
3327 mutex_init(&zilog
->zl_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
3328 mutex_init(&zilog
->zl_issuer_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
3329 mutex_init(&zilog
->zl_lwb_io_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
3331 for (int i
= 0; i
< TXG_SIZE
; i
++) {
3332 mutex_init(&zilog
->zl_itxg
[i
].itxg_lock
, NULL
,
3333 MUTEX_DEFAULT
, NULL
);
3336 list_create(&zilog
->zl_lwb_list
, sizeof (lwb_t
),
3337 offsetof(lwb_t
, lwb_node
));
3339 list_create(&zilog
->zl_itx_commit_list
, sizeof (itx_t
),
3340 offsetof(itx_t
, itx_node
));
3342 cv_init(&zilog
->zl_cv_suspend
, NULL
, CV_DEFAULT
, NULL
);
3343 cv_init(&zilog
->zl_lwb_io_cv
, NULL
, CV_DEFAULT
, NULL
);
3349 zil_free(zilog_t
*zilog
)
3353 zilog
->zl_stop_sync
= 1;
3355 ASSERT0(zilog
->zl_suspend
);
3356 ASSERT0(zilog
->zl_suspending
);
3358 ASSERT(list_is_empty(&zilog
->zl_lwb_list
));
3359 list_destroy(&zilog
->zl_lwb_list
);
3361 ASSERT(list_is_empty(&zilog
->zl_itx_commit_list
));
3362 list_destroy(&zilog
->zl_itx_commit_list
);
3364 for (i
= 0; i
< TXG_SIZE
; i
++) {
3366 * It's possible for an itx to be generated that doesn't dirty
3367 * a txg (e.g. ztest TX_TRUNCATE). So there's no zil_clean()
3368 * callback to remove the entry. We remove those here.
3370 * Also free up the ziltest itxs.
3372 if (zilog
->zl_itxg
[i
].itxg_itxs
)
3373 zil_itxg_clean(zilog
->zl_itxg
[i
].itxg_itxs
);
3374 mutex_destroy(&zilog
->zl_itxg
[i
].itxg_lock
);
3377 mutex_destroy(&zilog
->zl_issuer_lock
);
3378 mutex_destroy(&zilog
->zl_lock
);
3379 mutex_destroy(&zilog
->zl_lwb_io_lock
);
3381 cv_destroy(&zilog
->zl_cv_suspend
);
3382 cv_destroy(&zilog
->zl_lwb_io_cv
);
3384 kmem_free(zilog
, sizeof (zilog_t
));
3388 * Open an intent log.
3391 zil_open(objset_t
*os
, zil_get_data_t
*get_data
)
3393 zilog_t
*zilog
= dmu_objset_zil(os
);
3395 ASSERT3P(zilog
->zl_get_data
, ==, NULL
);
3396 ASSERT3P(zilog
->zl_last_lwb_opened
, ==, NULL
);
3397 ASSERT(list_is_empty(&zilog
->zl_lwb_list
));
3399 zilog
->zl_get_data
= get_data
;
3405 * Close an intent log.
3408 zil_close(zilog_t
*zilog
)
3413 if (!dmu_objset_is_snapshot(zilog
->zl_os
)) {
3414 zil_commit(zilog
, 0);
3416 ASSERT3P(list_tail(&zilog
->zl_lwb_list
), ==, NULL
);
3417 ASSERT0(zilog
->zl_dirty_max_txg
);
3418 ASSERT3B(zilog_is_dirty(zilog
), ==, B_FALSE
);
3421 mutex_enter(&zilog
->zl_lock
);
3422 lwb
= list_tail(&zilog
->zl_lwb_list
);
3424 txg
= zilog
->zl_dirty_max_txg
;
3426 txg
= MAX(zilog
->zl_dirty_max_txg
, lwb
->lwb_max_txg
);
3427 mutex_exit(&zilog
->zl_lock
);
3430 * zl_lwb_max_issued_txg may be larger than lwb_max_txg. It depends
3431 * on the time when the dmu_tx transaction is assigned in
3432 * zil_lwb_write_issue().
3434 mutex_enter(&zilog
->zl_lwb_io_lock
);
3435 txg
= MAX(zilog
->zl_lwb_max_issued_txg
, txg
);
3436 mutex_exit(&zilog
->zl_lwb_io_lock
);
3439 * We need to use txg_wait_synced() to wait until that txg is synced.
3440 * zil_sync() will guarantee all lwbs up to that txg have been
3441 * written out, flushed, and cleaned.
3444 txg_wait_synced(zilog
->zl_dmu_pool
, txg
);
3446 if (zilog_is_dirty(zilog
))
3447 zfs_dbgmsg("zil (%px) is dirty, txg %llu", zilog
,
3449 if (txg
< spa_freeze_txg(zilog
->zl_spa
))
3450 VERIFY(!zilog_is_dirty(zilog
));
3452 zilog
->zl_get_data
= NULL
;
3455 * We should have only one lwb left on the list; remove it now.
3457 mutex_enter(&zilog
->zl_lock
);
3458 lwb
= list_head(&zilog
->zl_lwb_list
);
3460 ASSERT3P(lwb
, ==, list_tail(&zilog
->zl_lwb_list
));
3461 ASSERT3S(lwb
->lwb_state
, !=, LWB_STATE_ISSUED
);
3463 if (lwb
->lwb_fastwrite
)
3464 metaslab_fastwrite_unmark(zilog
->zl_spa
, &lwb
->lwb_blk
);
3466 list_remove(&zilog
->zl_lwb_list
, lwb
);
3467 zio_buf_free(lwb
->lwb_buf
, lwb
->lwb_sz
);
3468 zil_free_lwb(zilog
, lwb
);
3470 mutex_exit(&zilog
->zl_lock
);
3473 static char *suspend_tag
= "zil suspending";
3476 * Suspend an intent log. While in suspended mode, we still honor
3477 * synchronous semantics, but we rely on txg_wait_synced() to do it.
3478 * On old version pools, we suspend the log briefly when taking a
3479 * snapshot so that it will have an empty intent log.
3481 * Long holds are not really intended to be used the way we do here --
3482 * held for such a short time. A concurrent caller of dsl_dataset_long_held()
3483 * could fail. Therefore we take pains to only put a long hold if it is
3484 * actually necessary. Fortunately, it will only be necessary if the
3485 * objset is currently mounted (or the ZVOL equivalent). In that case it
3486 * will already have a long hold, so we are not really making things any worse.
3488 * Ideally, we would locate the existing long-holder (i.e. the zfsvfs_t or
3489 * zvol_state_t), and use their mechanism to prevent their hold from being
3490 * dropped (e.g. VFS_HOLD()). However, that would be even more pain for
3493 * if cookiep == NULL, this does both the suspend & resume.
3494 * Otherwise, it returns with the dataset "long held", and the cookie
3495 * should be passed into zil_resume().
3498 zil_suspend(const char *osname
, void **cookiep
)
3502 const zil_header_t
*zh
;
3505 error
= dmu_objset_hold(osname
, suspend_tag
, &os
);
3508 zilog
= dmu_objset_zil(os
);
3510 mutex_enter(&zilog
->zl_lock
);
3511 zh
= zilog
->zl_header
;
3513 if (zh
->zh_flags
& ZIL_REPLAY_NEEDED
) { /* unplayed log */
3514 mutex_exit(&zilog
->zl_lock
);
3515 dmu_objset_rele(os
, suspend_tag
);
3516 return (SET_ERROR(EBUSY
));
3520 * Don't put a long hold in the cases where we can avoid it. This
3521 * is when there is no cookie so we are doing a suspend & resume
3522 * (i.e. called from zil_vdev_offline()), and there's nothing to do
3523 * for the suspend because it's already suspended, or there's no ZIL.
3525 if (cookiep
== NULL
&& !zilog
->zl_suspending
&&
3526 (zilog
->zl_suspend
> 0 || BP_IS_HOLE(&zh
->zh_log
))) {
3527 mutex_exit(&zilog
->zl_lock
);
3528 dmu_objset_rele(os
, suspend_tag
);
3532 dsl_dataset_long_hold(dmu_objset_ds(os
), suspend_tag
);
3533 dsl_pool_rele(dmu_objset_pool(os
), suspend_tag
);
3535 zilog
->zl_suspend
++;
3537 if (zilog
->zl_suspend
> 1) {
3539 * Someone else is already suspending it.
3540 * Just wait for them to finish.
3543 while (zilog
->zl_suspending
)
3544 cv_wait(&zilog
->zl_cv_suspend
, &zilog
->zl_lock
);
3545 mutex_exit(&zilog
->zl_lock
);
3547 if (cookiep
== NULL
)
3555 * If there is no pointer to an on-disk block, this ZIL must not
3556 * be active (e.g. filesystem not mounted), so there's nothing
3559 if (BP_IS_HOLE(&zh
->zh_log
)) {
3560 ASSERT(cookiep
!= NULL
); /* fast path already handled */
3563 mutex_exit(&zilog
->zl_lock
);
3568 * The ZIL has work to do. Ensure that the associated encryption
3569 * key will remain mapped while we are committing the log by
3570 * grabbing a reference to it. If the key isn't loaded we have no
3571 * choice but to return an error until the wrapping key is loaded.
3573 if (os
->os_encrypted
&&
3574 dsl_dataset_create_key_mapping(dmu_objset_ds(os
)) != 0) {
3575 zilog
->zl_suspend
--;
3576 mutex_exit(&zilog
->zl_lock
);
3577 dsl_dataset_long_rele(dmu_objset_ds(os
), suspend_tag
);
3578 dsl_dataset_rele(dmu_objset_ds(os
), suspend_tag
);
3579 return (SET_ERROR(EACCES
));
3582 zilog
->zl_suspending
= B_TRUE
;
3583 mutex_exit(&zilog
->zl_lock
);
3586 * We need to use zil_commit_impl to ensure we wait for all
3587 * LWB_STATE_OPENED and LWB_STATE_ISSUED lwbs to be committed
3588 * to disk before proceeding. If we used zil_commit instead, it
3589 * would just call txg_wait_synced(), because zl_suspend is set.
3590 * txg_wait_synced() doesn't wait for these lwb's to be
3591 * LWB_STATE_FLUSH_DONE before returning.
3593 zil_commit_impl(zilog
, 0);
3596 * Now that we've ensured all lwb's are LWB_STATE_FLUSH_DONE, we
3597 * use txg_wait_synced() to ensure the data from the zilog has
3598 * migrated to the main pool before calling zil_destroy().
3600 txg_wait_synced(zilog
->zl_dmu_pool
, 0);
3602 zil_destroy(zilog
, B_FALSE
);
3604 mutex_enter(&zilog
->zl_lock
);
3605 zilog
->zl_suspending
= B_FALSE
;
3606 cv_broadcast(&zilog
->zl_cv_suspend
);
3607 mutex_exit(&zilog
->zl_lock
);
3609 if (os
->os_encrypted
)
3610 dsl_dataset_remove_key_mapping(dmu_objset_ds(os
));
3612 if (cookiep
== NULL
)
3620 zil_resume(void *cookie
)
3622 objset_t
*os
= cookie
;
3623 zilog_t
*zilog
= dmu_objset_zil(os
);
3625 mutex_enter(&zilog
->zl_lock
);
3626 ASSERT(zilog
->zl_suspend
!= 0);
3627 zilog
->zl_suspend
--;
3628 mutex_exit(&zilog
->zl_lock
);
3629 dsl_dataset_long_rele(dmu_objset_ds(os
), suspend_tag
);
3630 dsl_dataset_rele(dmu_objset_ds(os
), suspend_tag
);
3633 typedef struct zil_replay_arg
{
3634 zil_replay_func_t
*const *zr_replay
;
3636 boolean_t zr_byteswap
;
3641 zil_replay_error(zilog_t
*zilog
, const lr_t
*lr
, int error
)
3643 char name
[ZFS_MAX_DATASET_NAME_LEN
];
3645 zilog
->zl_replaying_seq
--; /* didn't actually replay this one */
3647 dmu_objset_name(zilog
->zl_os
, name
);
3649 cmn_err(CE_WARN
, "ZFS replay transaction error %d, "
3650 "dataset %s, seq 0x%llx, txtype %llu %s\n", error
, name
,
3651 (u_longlong_t
)lr
->lrc_seq
,
3652 (u_longlong_t
)(lr
->lrc_txtype
& ~TX_CI
),
3653 (lr
->lrc_txtype
& TX_CI
) ? "CI" : "");
3659 zil_replay_log_record(zilog_t
*zilog
, const lr_t
*lr
, void *zra
,
3662 zil_replay_arg_t
*zr
= zra
;
3663 const zil_header_t
*zh
= zilog
->zl_header
;
3664 uint64_t reclen
= lr
->lrc_reclen
;
3665 uint64_t txtype
= lr
->lrc_txtype
;
3668 zilog
->zl_replaying_seq
= lr
->lrc_seq
;
3670 if (lr
->lrc_seq
<= zh
->zh_replay_seq
) /* already replayed */
3673 if (lr
->lrc_txg
< claim_txg
) /* already committed */
3676 /* Strip case-insensitive bit, still present in log record */
3679 if (txtype
== 0 || txtype
>= TX_MAX_TYPE
)
3680 return (zil_replay_error(zilog
, lr
, EINVAL
));
3683 * If this record type can be logged out of order, the object
3684 * (lr_foid) may no longer exist. That's legitimate, not an error.
3686 if (TX_OOO(txtype
)) {
3687 error
= dmu_object_info(zilog
->zl_os
,
3688 LR_FOID_GET_OBJ(((lr_ooo_t
*)lr
)->lr_foid
), NULL
);
3689 if (error
== ENOENT
|| error
== EEXIST
)
3694 * Make a copy of the data so we can revise and extend it.
3696 memcpy(zr
->zr_lr
, lr
, reclen
);
3699 * If this is a TX_WRITE with a blkptr, suck in the data.
3701 if (txtype
== TX_WRITE
&& reclen
== sizeof (lr_write_t
)) {
3702 error
= zil_read_log_data(zilog
, (lr_write_t
*)lr
,
3703 zr
->zr_lr
+ reclen
);
3705 return (zil_replay_error(zilog
, lr
, error
));
3709 * The log block containing this lr may have been byteswapped
3710 * so that we can easily examine common fields like lrc_txtype.
3711 * However, the log is a mix of different record types, and only the
3712 * replay vectors know how to byteswap their records. Therefore, if
3713 * the lr was byteswapped, undo it before invoking the replay vector.
3715 if (zr
->zr_byteswap
)
3716 byteswap_uint64_array(zr
->zr_lr
, reclen
);
3719 * We must now do two things atomically: replay this log record,
3720 * and update the log header sequence number to reflect the fact that
3721 * we did so. At the end of each replay function the sequence number
3722 * is updated if we are in replay mode.
3724 error
= zr
->zr_replay
[txtype
](zr
->zr_arg
, zr
->zr_lr
, zr
->zr_byteswap
);
3727 * The DMU's dnode layer doesn't see removes until the txg
3728 * commits, so a subsequent claim can spuriously fail with
3729 * EEXIST. So if we receive any error we try syncing out
3730 * any removes then retry the transaction. Note that we
3731 * specify B_FALSE for byteswap now, so we don't do it twice.
3733 txg_wait_synced(spa_get_dsl(zilog
->zl_spa
), 0);
3734 error
= zr
->zr_replay
[txtype
](zr
->zr_arg
, zr
->zr_lr
, B_FALSE
);
3736 return (zil_replay_error(zilog
, lr
, error
));
3742 zil_incr_blks(zilog_t
*zilog
, const blkptr_t
*bp
, void *arg
, uint64_t claim_txg
)
3744 (void) bp
, (void) arg
, (void) claim_txg
;
3746 zilog
->zl_replay_blks
++;
3752 * If this dataset has a non-empty intent log, replay it and destroy it.
3755 zil_replay(objset_t
*os
, void *arg
,
3756 zil_replay_func_t
*const replay_func
[TX_MAX_TYPE
])
3758 zilog_t
*zilog
= dmu_objset_zil(os
);
3759 const zil_header_t
*zh
= zilog
->zl_header
;
3760 zil_replay_arg_t zr
;
3762 if ((zh
->zh_flags
& ZIL_REPLAY_NEEDED
) == 0) {
3763 zil_destroy(zilog
, B_TRUE
);
3767 zr
.zr_replay
= replay_func
;
3769 zr
.zr_byteswap
= BP_SHOULD_BYTESWAP(&zh
->zh_log
);
3770 zr
.zr_lr
= vmem_alloc(2 * SPA_MAXBLOCKSIZE
, KM_SLEEP
);
3773 * Wait for in-progress removes to sync before starting replay.
3775 txg_wait_synced(zilog
->zl_dmu_pool
, 0);
3777 zilog
->zl_replay
= B_TRUE
;
3778 zilog
->zl_replay_time
= ddi_get_lbolt();
3779 ASSERT(zilog
->zl_replay_blks
== 0);
3780 (void) zil_parse(zilog
, zil_incr_blks
, zil_replay_log_record
, &zr
,
3781 zh
->zh_claim_txg
, B_TRUE
);
3782 vmem_free(zr
.zr_lr
, 2 * SPA_MAXBLOCKSIZE
);
3784 zil_destroy(zilog
, B_FALSE
);
3785 txg_wait_synced(zilog
->zl_dmu_pool
, zilog
->zl_destroy_txg
);
3786 zilog
->zl_replay
= B_FALSE
;
3790 zil_replaying(zilog_t
*zilog
, dmu_tx_t
*tx
)
3792 if (zilog
->zl_sync
== ZFS_SYNC_DISABLED
)
3795 if (zilog
->zl_replay
) {
3796 dsl_dataset_dirty(dmu_objset_ds(zilog
->zl_os
), tx
);
3797 zilog
->zl_replayed_seq
[dmu_tx_get_txg(tx
) & TXG_MASK
] =
3798 zilog
->zl_replaying_seq
;
3806 zil_reset(const char *osname
, void *arg
)
3810 int error
= zil_suspend(osname
, NULL
);
3811 /* EACCES means crypto key not loaded */
3812 if ((error
== EACCES
) || (error
== EBUSY
))
3813 return (SET_ERROR(error
));
3815 return (SET_ERROR(EEXIST
));
3819 EXPORT_SYMBOL(zil_alloc
);
3820 EXPORT_SYMBOL(zil_free
);
3821 EXPORT_SYMBOL(zil_open
);
3822 EXPORT_SYMBOL(zil_close
);
3823 EXPORT_SYMBOL(zil_replay
);
3824 EXPORT_SYMBOL(zil_replaying
);
3825 EXPORT_SYMBOL(zil_destroy
);
3826 EXPORT_SYMBOL(zil_destroy_sync
);
3827 EXPORT_SYMBOL(zil_itx_create
);
3828 EXPORT_SYMBOL(zil_itx_destroy
);
3829 EXPORT_SYMBOL(zil_itx_assign
);
3830 EXPORT_SYMBOL(zil_commit
);
3831 EXPORT_SYMBOL(zil_claim
);
3832 EXPORT_SYMBOL(zil_check_log_chain
);
3833 EXPORT_SYMBOL(zil_sync
);
3834 EXPORT_SYMBOL(zil_clean
);
3835 EXPORT_SYMBOL(zil_suspend
);
3836 EXPORT_SYMBOL(zil_resume
);
3837 EXPORT_SYMBOL(zil_lwb_add_block
);
3838 EXPORT_SYMBOL(zil_bp_tree_add
);
3839 EXPORT_SYMBOL(zil_set_sync
);
3840 EXPORT_SYMBOL(zil_set_logbias
);
3842 ZFS_MODULE_PARAM(zfs
, zfs_
, commit_timeout_pct
, INT
, ZMOD_RW
,
3843 "ZIL block open timeout percentage");
3845 ZFS_MODULE_PARAM(zfs_zil
, zil_
, replay_disable
, INT
, ZMOD_RW
,
3846 "Disable intent logging replay");
3848 ZFS_MODULE_PARAM(zfs_zil
, zil_
, nocacheflush
, INT
, ZMOD_RW
,
3849 "Disable ZIL cache flushes");
3851 ZFS_MODULE_PARAM(zfs_zil
, zil_
, slog_bulk
, ULONG
, ZMOD_RW
,
3852 "Limit in bytes slog sync writes per commit");
3854 ZFS_MODULE_PARAM(zfs_zil
, zil_
, maxblocksize
, INT
, ZMOD_RW
,
3855 "Limit in bytes of ZIL log block size");